2,962 terms

All APBIO Ch. 1-55 (Pretty EPIC)

A combination of all the sets I have made including all chapters from 1 to 55, you will have to go to the group in order to get The important Diseases Set, but otherwise this is the Magna Carta (2962)
A conserved sequence of 60 amino acids used in the binding to DNA. Usually found in transcription factors, it is used to express genes that are related, more specifically in development to make tissues associated with one another.
Model Organism
An organism selected for intensive scientific study based on features that make it easy to work with (e.g., body size, life span), in the hope that findings will apply to other species.
eukaryotes are genetic ____, they havae combined genomes of at least three different prokayroyes.
The development of body shape and organization.
Cell Differentiation
The structural and functional divergence of cells as they become specialized during a multicellular organism's development; dependent on the control of gene expression.
Cell Division
the process in reproduction and growth by which a cell divides to form daughter cells
An embryonic stage in animal development encompassing the formation of three layers: ectoderm, mesoderm, and endoderm.
The hollow ball of cells marking the end stage of cleavage during early embryonic development
In animal development, a series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo, the gastrula.
a type of cell death in which the cell uses specialized cellular machinery to kill itself
Cell Lineage
entire ancestry of every cell in the body of an adult (Like that of C. Elegens), usually represented over time in a pedigree.
Stem Cell
an undifferentiated cell whose daughter cells may differentiate into other cell types (such as blood cells)
Plant tissue that remains embryonic as long as the plant lives, allowing for indeterminate growth.
Gene Expression
the activation or "turning on" of a gene that results in transcription and the production of mRNA
Genomic Equivalence
That each somatic cell in an organism has the same set of gene's
Found that undeffirentiated carrot cells could be used to make any part of the carrot, or develop into an adult plant.(Totipotent)
Describing a cell that can give rise to all parts of the embryo and adult, as well as extraembryonic membranes in species that have them.
Nuclear Transplantation
a technique in which the nucleus of one cell(usually undifferentiated) is placed into another cell that already has a nucleus(differntiated) or in which the nucleus has been previously destroyed, inversly related to the age of the donor(becasue of acetylation, methylation etc etc.
Reproductive Cloning
The process of implanting an early embryo into the uterus of a surrogate mother. The resulting animal will be genetically identical to the donor of the nucleus.
cells that are capable of developing into most, but not all, of the body's cell types
A fluid-filled sphere formed about 5 days after fertilization of an ovum that is made up of an outer ring of cells and inner cell mass. THis is the structure that implants in the endometrium of the uterus.
Therapeutic Cloning
the cloning of human cells by nuclear transplantation for therapeutic purposes, such as the generation of embryonic stem cells
The progressive restriction of developmental potential, causing the possible fate of each cell to become more limited as the embryo develops. Maked by the expression of certain tissue expression proteins
Tissue Specific proteins
found only in a specific cell type and give the cell thats characteristic structure and function.
An embryonic cell that develops into a cell of muscle fiber
The most abundant plasma protein, 60% of the total protein, made by the liver, plays an important role in osmotic balance, contributes to the viscosity of blood, transportation of lipids/hormones/calcium..., and helps to maintain pH
Transparent proteins in lens fibers that are responsible for the clarity and focusing power of the lens
Cytoplasmic Determinant
A maternal substance, such as protein or RNA, that influences the course of early development by regulating the expression of genes that affect the developmental fate of cells.
a transcription factor that binds to enhancers of various target, produces transcription factor that binds to the promoters of genes that produce features of skeletal muscle cells
The process in which one group of embryonic cells influences the development of another, usually by causing changes in gene expression involving the movement of certain signal molecules..
Body Plan
In animals, a set of morphological and developmental traits that are integrated into a functional whole—the living animal.
Pattern Formation
The development of a multicellular organism's spatial organization, the arrangement of organs and tissues in their characteristic places in three-dimensional space.
Positional Information
Molecular cues that control pattern formation in an animal or plant embryonic structure by indicating a cell's location relative to the organism's body axes. These cues elicit a response by genes that regulate development.
Multinucleate Cell
During the first 10 quick mitotic divisions in an Drosophila melanogaster, there are S and M phases only with no growt, so the amount of cytoplasm does NOT change, making it a _____________.
an embryonic cap of dividing cells resting on a large undivided yolk
Edward Lewis
(1) studied developmental mutations in organisms and linked them to specific genes, (2) first researcher to notice mutations in Drosophila that affected the correct placement of body parts and therefore had to be mutants in the development process, (3) when he performed test crosses with antennapedia mutants, he found that the mutation was inherited as a recessive trait
Embryonic Lethals
mutations with phenotype causing death at the the embryonic or larval stage
Maternal Effect Gene
A gene that, when mutant in the mother, results in a mutant phenotype in the offspring, regardless of the genotype. AKA egg polarity genes.
Egg Polarity Genes
Another name for maternal effect genes, these genes control the orientation (polarity) of the egg, one group sets up the anterior posterior axis, while the other sets up the dorsal ventrtal axis.
A maternal effect gene that codes for a protein responsible for specifying the anterior(head) end in Drosophilia. A defect in this will lead to two posterior ends being formed, and is due to a gradient of the mRNA (morphogens) expressed in one part of the body.
A substance that provides positional information in the form of a concentration gradient along an embryonic axis.
Segmentation Genes
the genes of the embryo whose products direct formation of segments after the embryo's major body axes are defined by egg polarity genes.
Homeotic Genes
determine such basic features as where a pair of wings and a pair of legs will develop on a bird or how a plant's flower parts are arranged
Gap Genes
Mutations in these genes cause "gaps" in Drosophila segmentation. The normal gene products map out the basic subdivisions along the anterior-posterior axis of the embryo.
Pair Rule Genes
Genes that define the modular patterns in terms of pairs of segments in Drosophila. Mutations in these genes result in embryos with half the normal segment number because every other segment fails to develop.
Segment Polarity Genes
establish anterior-posterior gradient with each segment
the whole cell shrinks and becomes lobed
Ced -3
C. elegan caspase protein that causes apoptosis via the ced-3/ced4 complex which is upregulated by inhibitor ced-9.
Cytochrome C
loss of mitochondrial membrane potential will release substances like ____ which activate caspases
a family of cysteine-dependent, aspartate-specific proteases that are associated with apoptosis in neurodegenerative diseases
Evo Devo
Evolutionary developmental biology; a field of biology that compares developmental processes of different multicellular organisms to understand how these processes have evolved and how changes can modify existing organismal features or lead to new ones.
A 180-nucleotide sequence within a homeotic gene encoding the part of the protein that binds to the DNA of the genes regulated by the protein., and specifies a 60 amino acid homeodomain.
Hox Genes
series of genes that controls the differentiation of cells and tissues in an embryo
Mads Box Genes
a conserved sequence motif found in a family of transcription factors, the MADS-box protein family. The length of the MADS-box reported typically varies in the range of 168 to 180 bp.Found mainly in plants(ABC MODEL)
Gene Therapy
The insertion of working copies of a gene into the cells of a person with a genetic disorder in an attempt to correct the disorder, for it to be permanent it must involve the cells that will proliferate throughout a persons lifetime(like BONE Marrow Cells)
Human Genome Project
An international effort to map the complete human genetic code. This effort was essentially completed in 2001, though analysis is ongoing.
In Vitro Fertilization
The most common assisted reproduction procedure, in which a woman's eggs are mixed with sperm in culture dishes (in vitro) and then carefully inserted into a woman's uterus.
Golden Rice
Vitamin A deficiency is a serious health issue, so 2 genes from daffodils and 1 from bacteria were inserted, with added genes rice plants synthesize betacarotene, whtn the rice is eaten it is converted to Vitamin A
Recombinant DNA
Genetically engineered DNA made by recombining fragments of DNA from different organisms
Genetic Engineering
The direct manipulation of genes for practical purposes, which include the manufacture of protein products(like Hormones and blood clotting factors), by using this technological approach you can make recombinant DNA and then reintroduce it into cultured cells
A form of technology that uses living organisms, usually genes, to modify products, to make or modify plants and animals, or to develop other microorganisms for specific purposes.
Multicellular animals having cells differentiated into tissues and organs and usually a digestive cavity and nervous system
DNA Microarray
Technique used to screen a single sample for a vast range of different nucleotide sequences stimultaneously; it is often used to study gene expression
Gene Cloning
The process of isolating a gene sequence in the genome of an organism and inserting the gene sequence into a plasmid vector for production in large numbers.
a diagram that shows the occurrence of a genetic trait in several generations of a family
Bacterial Plasmid
A Circular DNA molecule found in bacteria which can be inserted with foreign DNA.
Used to mass produce insulin and human growth hormone.
Recombinant Bacterium
Insert foreign DNA into a plasmid and then put the plasmid in a bacteria so it has foreign DNA too
a group of genetically identical cells or organisms derived from a single cell or individual by some kind of asexual reproduction
Cloned Genes
Are useful for two main purposes, they can be used to make many copies of a particular gene and can produce a protein product, which may endow an organism with a new metabolic function such as pest resistance.
Restriction Enzymes
Also called restriction endonucleases, were first discovered in the late 1960' s and have made genetic engineering possible. They are found naturally in Bacteria and protect against foreign organisms. Is very specific and only recognizes a particular DNA sequence
Restriction Fragments
DNA segment resulting from cutting of DNA by a restriction enzyme at a restriction site (Usually Many
Sticky Ends
Short, single-stranded regions of DNA that came from broken double-stranded palindromic DNA.
Restriction Sites
The DNA sequence that is recognized by a restriction enzyme; the restriction enzyme cuts at this sequence, generating two DNA fragments (Usually 4 to 8 Nucleotides) , and because it is so small, restriction fragments are cut out at many places.
DNA Ligase
An enzyme that catalyzes the formation of covalent bonds that close up the sugar phosphate backbone after the sticky ends form complementary hydrogen bonds(because these are only temporary)
Cloning Vector
An agent used to transfer DNA in genetic engineering. A plasmid from bacteria that moves recombinant DNA from a test tube back into a cell is an example , or it can be a virus that transfers recombinant DNA by infection.
Antibiotic resistance gene, found in vectors derived from natural episomes (plasmids) and bacterial genome.
Mech same as penicillin. Need a B-lactamase inhibitor. Used against Gram+ and HELPS (Haemophilus Influenza, E. Coli, Listeria, Proteus mirabilis, and Salmonella). SE: Pseudomembraneous Collitis (because of removal of gut bacteria). IV Form.
Gene part of the lac operon. If gene is intact, produces a product that can break down lactose and Xgal, and the colony WILL be blue. If not intact, it will NOTbreak down Xgal, colony will be white.
A Chemical similar to lactose that turns dark blue when cleaved by beta-galactosidase
a gel-like polysaccharide compound used for culturing microbes; extracted from certain red algae
The amount of cells that need to be present sothat they can be seen on an agar plate.
Nucleic Acid Hybridization
a form of DNA technology used to detect specific DNA or RNA sequences based on their ability to anneal to nucleic acid probes , if it know part of the neuclotide sequence of the gene of interest., then we could synthesize a probe that is complementary to it, which will then be labeled after it hydrgen bonds so that we could track it. KEY to this process is denaturazation of the Cell's DNA.
Nucleic Acid Probe
In DNA technology, a labeled single-stranded nucleic acid molecule used to locate a specific nucleotide sequence in a nucleic acid sample. Molecules of the probe hydrogen-bond to the complementary sequence wherever it occurs; radioactive or other labeling of the probe allows its location to be detected.
Genomic Library
A set of thousands of DNA segments from a genome, each carried by a plasmid, phage, or other cloning vector
Phage Library
Most efficient genome library, 160,000 are needed to make up human genome, made by the backaging of the recombinant DNA into bacterial cells, where they replicate and produce new phage particles, which are stored as a selection of phage clones.
Plasmid Library
Cannot contain much info, 700,000 are needed to make the human genome, made by a collection of bacterial cells each of which containing copies of a particular genome fragment
Complementary DNA
A DNA molecule made in vitro using (mRNA) as a TEMPLATE and the enzyme reverse transcriptase . Also called (cDNA) molecules , they corresponds to a gene, but LACK the introns present in the DNA of the genome. Useful for studying the specialized function of a particular cell type.
Reverse Transcriptase
An enzyme encoded by some certain viruses (retroviruses) that uses RNA as a template for DNA synthesis.
Expression Vector
A cloning vector that contains the requisite bacterial promoter just upstream of a restriction site where a eukaryotic gene can be inserted, allowing the gene to be expressed in a bacterial cell. Allowing for the synthesis of many eukaryotic proteins in bacterial cells.
yeast artificial chromosomes. They are linear, like normal yeast chromosomes, not circular like plasmids. They can be used to clone very large pieces of DNA, up to about 500 kbp. They are not used much anymore, as BAC clones have technical advantages., Can surmount the differential transciption between prokaryotes and Eukaryotes.
A technique to introduce recombinant DNA into cells by applying a brief electrical pulse to a solution containing cells. The electricity creates temporary holes in the cells' plasma membranes, through which DNA can enter.
A bacterium that forms Galls in plants and transfers some of its genes into plant chromosomes through conjugation
Polymerase Chain Reaction
A method of producing thousands of copies of DNA segment using the enzyme DNA polymerase(Usually From Archaea), it is especially useful when the amount of DNA present is very scant or impure, because it is a quicker(a couple billion in a couple of hours) and more selective. Requires Double Stranded DNA containing target sequence to be copied, heat resistant DNA Polymerase, all 4 Nucleotides, and two short,single stranded DNA molecules which will serve as primers. Problem becose of occasional errors.
Restriction Fragment Analysis
DNA fragments produced by restriction enzyme digestion of a DNA molecule are sorted by gel electrophoresis; is useful for comparing two different DNA molecules such as two allels for a gene; used to prepare pure samples of individual fragments
Gel Electrophoresis
A procedure used to separate and analyze DNA fragments by placing a mixture of DNA fragments at one end of a porous gel and applying an electrical voltage to the gel, the ones that are largest( or least negative) will move the slowest and farthest , while the smallest will do the exact opposite. These bands are NOT visible until a marker is added.
Southern Blotting
A technique that enables specific nucleotide sequences to be detected in a sample of DNA. It involves gel electrophoresis of DNA molecules and their transfer to a membrane (blotting), followed by nucleic acid hybridization with a labeled probe. (Must use an alakine solutiojn, Gel, Nitrocellulose, and a heavy weight to pull the solution through the cell. Most useful application is its use to identify the heterozygote carriers of mutant alleles associated with genetic diseases.
Differences in homologous DNA sequences that are reflected in different lengths of restriction fragments produced when the DNA is cut up with restriction enzymes
Physical Mapping
Assign genes to a particular locations using measurements that are a true reflection of the physical distance between the genes, usually by the number of base pairs along the DNA, which are then arranged so that they overlap
Linkage Mapping
Genes on a chromosome are arranged in a linear array, and the physical distance between them dictates the frequency of crossing over between them. The greater the physical distance,
the greater the frequency of crossing over. Made after a cytogenic maps are constructed by in situ hybridization.
Cytogenetic Map
a map of a chromosome that includes the positions of genes relative to visible chromosomal features, such as stained bands
Also called bacterial artificial chromosomes, which can clone much larger pieces of DNA but have lower copy number
Fredrick Sanger
the pioneer in determining the amino acid sequence of proteins, through his use of Dideoxy Chain Termination Method for Sequencing DNA .
Dideoxy Chain Termination Method
A method of determining a sequence of nucleotides in any CLONED DNA fragments up to 800 base pairs in length which can be determined rapidly by using a nested set of DNA strands complementary to the original DNA fragment, each that starts with the same primer and ends with Dideoxyriboneuclotide.(ddNTP), which terminates a growing DNA strand because it lacks a (OH-), and because they are tagged with a flourescent label , it determines the ending of the sequence which can be then used to sequence the entire DNA. (Developed by Fredrick Snger)
Hemophilus Influenzae
Gram- bacillus responsible for 5% of all bacterial meningitis cases,l also first complete genome sequenced by Vente and Celera Genomics
Celera Genomics
privately owned biotech company (Craig Venter)
techniques: relied on newer/faster DNA sequences & programs
Craig Venter
entreprenuer who worked for Celera. Developed the "Shotgun" sequencing method, wanted people to pay to view genes in database, raced against Francis Collins to Finish Genome
Shotgun Approach
• As genomes get larger, piecing together information gets more difficult.
• Typically used for smaller genomes, like bacteria.
• Early step is to fractionate DNA to that the fragments of the particular size are used.
o This is done by using a sonificator which breaks
the DNA into particular sizes that can be shown
on a gel and extracted and purified. The
end-sequences of DNA inserts are obtained and
put into computer to sequence them.
• Organizing the clones, you generate probes from the clones creating end-sequences and apply it to the entire genome. If the probe sticks to numerous places then you can attempt to say that they line up to each other in the genome.
study and comparison of genomes within a single species or among different species
Expressed Sequence Tags
certain short sequences that correspond to sequences present in known mRNA, are catalouged in a computer, which identifies sequences that are new product coding genes.
In Vitro Mutagenesis
A technique to discover the function of a gene by introducing specific changes into the sequence of a cloned gene, reinserting the mutated gene into a cell, and studying the phenotype of the mutant. RNAi is more effective and faster.
RNA interference; injecting double stranded RNA into a cell turns off expression of a gene with the same sequence as the RNA, useful in assesing differential expression of genes.
DNA microarray assays
A method to detect and measure the expression of thousands of genes at one time. Tiny amounts of a large number of single-stranded DNA fragments representing different genes are fixed to a glass slide. These fragments, ideally representing all the genes of an organism, are tested for hybridization with various samples of cDNA molecules.
the full protein sets encoded by genomes
the study of all of an organism's proteins, including its identity, structure, interaction, and abundance
a DNA sequence variation occurring when a single nucleotide — A, T, C, or G — in the genome (or other shared sequence) differs between members of a species (or between paired chromosomes in an individual). For example, two sequenced DNA fragments from different individuals, AAGCCTA to AAGCTTA, contain a difference in a single nucleotide. In this case we say that there are two alleles : C and T. Frequency may vary with ethnicity
is a variant of polymerase chain reaction (PCR), a laboratory technique commonly used in molecular biology to generate many copies of a DNA sequence, a process termed "amplification". An RNA strand is first reverse transcribed into its DNA complement (complementary DNA, or cDNA) using the enzyme reverse transcriptase, and the resulting cDNA
Severe combined immuno-deficiency. In this disorder both B-cells and T-cells are absent and therefore such babies are highly susceptible even to minor infections.
(Human growth hormone) also known as somatotrophic hormone is responsible for the growth of long bones, muscles and viscera.
Tissue Plasminogen Activator
converts PLASMINOGEN to PLASMIN in the presence of fibrin ,may lose fibrin specificity at high doses which disolves clots(Like in the case of a heart attck) and bleeding is common
DNA Fingerprints
Compares repeated sections of genes that have little to no known function, but vaary widley from one person to another(STRs). gel electrophoresis used to separate fragments, the specific repeats are then labeled using radioactive probes producing bands to e compared
Short Tandem Repeats, regions of a DNA molecule that contain short segments consisting of three to seven repeating base pairs
term used to refer to an organism that contains genes from other organisms
Ti Plasmid
a plasmid of a tumor-inducing bacterium that integrates a segment of its DNA into a chromosome of a host plants. frequently used as a vector for genetic engineering in plants. Comes form Agrobacterium tumefaciens
Genetically Modified Organisms
organisms whose genetic code has been altered by artificial means such as interspecies gene transfer
foreign gene that is transferred into target cell or tissue
a strech of DNA found in a Ti plasmid, INJECTED IN THE CHROMOSOMAL dna of its host.
a sclerenchyma cell with a thick, lignified secondary wall having many pits. sclereids are variable inf orm but typically not very long; they may or may not be living at maturity- seed coats, nutshells
Member of a clade consisting of the vast majority of flowering plants that have two embryonic seed leaves, or cotyledons. Taprrot System, lateral root divergence, vascular bundles arranged in a ring. Multiple of 5
an organism's ability to alter itself in response to local environmental conditions, Can Be seen in the brain), plants.
the branch of biology that deals with the structure of animals and plants
A group of cells with a common function or structure.
Common aquatic plant of eastern North America having floating and submerged leaves and white yellow-spotted flowers
a collection of tissues that carry out a specialized function of the body
Root System
All of a plant's roots, which anchor it in the soil, absorb and transport minerals and water, and store food, have root hairs that significantly increase surface area and thus making the water transport more massive and efficent.
Shoot System
The aerial portion of a plant body, consisting of stems, leaves, and (in angiosperms) flowers. Main Photosyntheistic components take place here.
An organ in vascular plants that anchors the plant and enables it to absorb water and nutrients from the soil. In Eudicots and Gymosperms(Taproot) ,and Most mono cots and seedless Vascular (fibrous)
A vascular plant organ consisting of an alternating system of nodes and internodes that support the leaves and reproductive structures.
photosynthetic organ that contains one or more bundles of vascular tissue
Taproot System
A root system common to eudicots, consisting of one large, vertical root (the taproot) that produces many smaller lateral, or branch, roots.
Fibrous Root System
Root systems common to monocots consisting of a mat of thin roots that spread out below the soil surface. (Described as bring Adventitous)
Lateral Roots
A root that arises from the outermost layer of the pericycle of an established root. Allso called branched roots they are usually on the outside of taproots in Eudicots.
A clade consisting of flowering plants that have one embyonic seed leaf, or cotyledon. Flower parts in multiples of 3. Parellel Vein Structure
Root Tip
Made up of the root cap, meristematic zone, elongation zone, and maturation zone, where most of the water is absorbed/
Root Hair
A tiny extension of a root epidermal cell, growing just behind the root tip and increasing surface area for absorption of water and minerals.
Prop Roots
Thick adventitious roots that grow from the lower part of the stem and brace the plant.
Storage Roots
many plants, such as the common beet, store food and water in these type of roots.
Buttress Roots
Large wall-like flanks that grow out from trees to brace the trunks; angular, open enclosures, ready habitat for animals. Found in tropical rainforests. (Ceiba Tree)
(air roots) produced by trees that inhabit tidal swamps. By projecting above the water's surface, they enable the root system to obtain oxygen.
a point along the stem of a plant at which leaves are attached.
A segment of a plant stem between the points where leaves are attached.
Axillary Bud
A structure that has the potential to form a lateral shoot, or branch. The bud appears in the angle formed between a leaf and a stem.
Lateral Shoot
an offshoot of the stem of the plant; fancy name for branch
Terminal Bud
Embryonic tissue at the tip of a shoot, made up of developing leaves and a compact series of nodes and internodes.
Apical Dominance
Concentration of growth at the tip of a plant shoot, where a terminal bud partially inhibits axillary bud growth.
The flattened portion of a typical leaf
The stalk of a leaf, which joins the leaf to a node of the stem.
plants formed from natural asexual reproduction that have buds that produce plantlets underground, i.e. potatoes and artichokes
short, underground stem that's surrounded by leaves that contain stored food (occurs in tulips, lilies and onions)
Underground stems that anchor a fern and absorb water
Simple Leaf
leaf with a single blade, i.e. grass, maple leaves, oak leaves
Compound Leaf
a type of leaf that consists of a petiole and two or more leaf blades called leaflets
Doubly Compound Leaf
each leaflet in this type of leaf is divided into smaller leaflets
A twisting, threadlike structure by which a twining plant (vine) grasps an object for support (modified leaf)
In plants, modified leaves that are stiff and sharp and that function in defense.
modified leaves with bright color that serve the same function of petals in attracting pollinators
Reproductive Leaves
Leaf modification: These produce tiny plants along the leaf margins that fall to the ground and take root in the soil.
Tissue System
One or more tissues organized into a functional unit connecting the organs of a plant
Dermal Tissue System
The protective covering of plants; generally a single layer of tightly packed epidermal cells covering young plant organs formed by primary growth.
The dermal tissue system of nonwoody plants, usually consisting of a single layer of tightly packed cells.
The protective coat that replaces the epidermis in woody plants during secondary growth, formed of the cork and cork cambium.
Vascular Tissue System
A system formed by xylem and phloem throughout a vascular plant, serving as a long distant transport system for water and nutrients, respectively.
The woody part of plants: the supporting and water-conducting tissue, consisting primarily of tracheids and vessels
Vascular tissue responsible for the transport of nutrients and the carbohydrates produced by photosynthesis
Vascular Cylinder
The central cylinder of vascular tissue in a plant root., -a region completely enclosed by the endodermis.(Especially in angiosperm the stele is also completely enclosed)
Vascular Bundles
strands of vascular tissue that run the length of the stem
Ground Tissue System
Plant tissues that are neither vascular nor dermal, fulfilling a variety of functions, such as storage, photosynthesis, and support. Internal(pith)
parenchyma cells inside the ring of vascular tissue in dicot stems
Ground tissue that is between the vascular tissue and dermal tissue in a root or dicot stem.
A waxy covering on the surface of stems and leaves that acts as an adaptation to prevent desiccation in terrestrial plants.
Primary Growth
Growth produced by apical meristems, which lengthen stems and roots.
Secondary Growth
Growth produced by lateral meristems, which thickens the roots and shoots of woody plants, increasing the girth by making periderm.
Leaf Trichomes
Outgrowths of the epidermis ,
A water-conducting and supportive element of xylem composed of long, thin cells with tapered ends and walls hardened with lignin.
vascular tissue of a root or stem
A hard material embedded in the cellulose matrix of vascular plant cell walls that functions as an important adaptation for support in terrestrial species.
the contents of a plant cell exclusive of the cell wall
"Typical Plant Cells" less specialization, relatively thin, flexible primary plant cell walls(most LACK secondary cell walls), Perform most of the metabolic functions of the plant.(photosynthesis within chloroplasts), colorless plastids that store starch, fleshy tissue, retain ability to differentiate.
Collenchyma Cells
Plant cells that are grouped in strands and cylinders, have very unevenly thickened primary cell walls(help support plant). Usually located just below the epidermis, LACK lignin and secondary cell walls, and are flexible because of it.
Sclerenchyma Cells
Are the only cells with THICK secondary cell walls strengthed by lignin, and because of this are much more rigid than collenchyma cells. Cannot elongate, and are so specialized that most are dead at functional maturity. 2 Types of cells Sclereids (short,irregular, thickened and lignified-seed coats nutshells) and Fibers(long, slender and tapered- hemp, flax)
A lignified cell type that reinforces the xylem of angiosperms and functions in mechanical support; a slender, tapered sclerenchyma cell that usually occurs in bundles. (Flax, hemp)
Water Conducting Cells
Composed of tracheids(long thin with tapered ends) and vessel elements(wider, shorter, thinner walled and less tapered, with perferoations), these both have rigid, lignin-containing secondary cell walls, interrupted by pits
Vessel Elements
A short, wide, water conducting cell found in the xylem of most angiosperms and a few nonflowering vascular plants. Dead at maturity, vessel elements are aligned end to form micropipes called vessels.
Continuous water-conducting micropipes found in most angiosperms and a few nonflowering vascular plants.
Sugar Conducting Cells
In phloem, live at functional maturity, function in sugar transport. 2 types Sieve- Tube members and Companion Cells.
Sieve-Tube members
A living cell that conducts sugars and other organic nutrients in the phloem of angiosperms. They form chains called sieve tubes., lack nucleus, ribosomes, and a distinct vacoule, the sieve plates on the end facilitate the flow of fliud
Sieve Plates
An end wall in a sieve-tube element, which facilitates the flow of phloem sap in angiosperm sieve tubes.
Companion Cells
nucleated cells that help manage the transport of sugars and other organic compounds through sieve cells, connected to sieve ube members by plamsodesmata
Open channels in the cell wall of a plant through which strands of cytosol connect from an adjacent cell.
Indeterminate Growth
A type of growth characteristic of plants, in which the organism continues to grow as long as it lives.
Determinate Growth
A type of growth characteristic of most animals and some plant organs, in which growth stops after a certain size is reached.
Plants that complete their life cycle- from germination to flowering to seed production to death- in a single year or less. Ex. wildflowers, staple food crops (legumes and cereal grains).
Anthophyte that flowers only after two years of growth. Beets and Carrots
Plants which live for years that survive by remaining dormant during the dry periods and come to life when water is available. Usually dies by infection.
Plant tissue that remains embryonic as long as the plant lives, allowing for indeterminate growth.
Apical Meristems
Embryonic plant tissue in the tips of roots and in the buds of shoots that supplies cells for the plant to grow in length, which allow the plant to grow in length ( primary growth)
Lateral Meristems
A meristem that thickens the roots and shoots of woody plants. The vascular cambium and cork cambium are lateral meristems.
Plants with stems that are non-woody and die back to the ground every year. Some herbaceous plants include marigolds, zinnias, grass, tomatoes, green beans and geraniums.
Vascular cambium
A cylinder of meristematic tissue in woody plants that adds layers of secondary vascular tissue called secondary xylem (wood) and secondary phloem.
Cork cambium
A cylinder of meristematic tissue in woody plants that replaces the epidermis with thicker, tougher cork cells.
Cells that remain as wellsprings of new cells in the meristem are called ---.
New cells that are displaced from an apical meristem and continue to divide until the cells they produce become specialized.
Primary Plant Body
The tissues produced by apical meristems, which lengthen stems and roots.
Root Cap
The thimble-shaped mass of cells covering and protecting the growing tip of a root as it pushes through the soil
Zone of Cell Division
The zone of primary growth in roots consisting of the root apical meristem and its derivatives. New root cells are produced in this region.
Zone of Elongation
The zone of primary growth in roots where new cells elongate, sometimes up to ten times their original length.
Zone of Maturation
The zone of primary growth in roots where cells complete their differentiation and become functionally mature.
first layer of cells (outermost) within the vascular cylinder, Where lateral roots arise from by puching through the cortex.
The innermost layer of the cortex in plant roots; a cylinder one cell thick that forms the boundary between the cortex and the vascular cylinder.
Leaf Primordia
Fingerlike projections along the flanks of a shoot apical meristem, from which leaves arise.
Intercalary Meristems
Found in monocots, actively produce new cells for increases in length, responsible for grass regrowing
Pore-like openings in leaves that allow gases (CO2 and O2) and water to diffuse in and out of the leaves.
opening in a leaf or a stem of a plant that enables gas exchange to occur
Guard Cell
specialized cell in the epidermis of plants that controls the opening and closing of stomata by responding to changes in water pressure
The ground tissue of a leaf, sandwiched between the upper and lower epidermis and specialized for photosynthesis.
Palisade Mesophyll
One or more layers of elongated photosynthetic cells on the upper part of a leaf; also called palisade parenchyma.
Spongy Mesophyll
Loosely arranged photosynthetic cells located below the palisade mesophyll cells in a leaf.
Leaf Traces
A small vascular bundle that extends from the vascular tissue of the stem through the petiole and into a leaf.
Bundle Sheath Cells
A type of photosynthetic cell arranged into tightly packed sheaths around the veins of a leaf. Usually consists of parenchyma.
Secondary Plant Body
The tissues produced by the vascular cambium and cork cambium, which thicken the stems and roots of woody plants.
Fusiform Initials
Cells within the vascular cambrium that produce elongated cells such as trocheids, vessel elements, fibers, and sieve-tube members.
Ray Initials
Cells within the vascular cambrium that produce xylem and phloem rays, radial files that consist mostly of parenchyma cells.
Located in the center portion of a tree trunk, it consists of older layers of secondary xylem
area in plants that surrounds heartwood and is active in fluid transport
In the stems of woody plants, a thin layer of cells located between the outer cork cells and inner cork cambium.
Fatty material found in the cell walls of cork tissue and in the Casparian strip of the endodermis
Small raised areas in the bark of stems and roots that enable gas exchange between living cells and the outside air.
Include all tissues that are external to the vascular cambium, not just the protective outer covering of plants.
The protective coat that replaces the epidermis in woody plants during secondary growth, formed of the cork and cork cambium.
Casparian Strip
A water-impermeable ring of wax around endodermal cells in plants that blocks the passive flow of water and solutes into the stele by way of cell walls
Systems Biology
An approach to studying biology that aims to model the dynamic behavior of whole biological systems.
the change in form of an organism resulting from cell differentiation
Asymmetrical Cell Division
produces two daughter cells with different properties; for example, one daughter cell received more cytoplasm that the other during mitosis
In plant cells only. In highly vacuolated plant cells, the nucleus has to migrate into the center of the cell before mitosis can begin. This is achieved through the formation of a phragmosome, a transverse sheet of cytoplasm that bisects the cell along the future plane of cell division. the formation of a ring of microtubules and actin filaments (called preprophase band) underneath the plasma membrane around the equatorial plane of the future mitotic spindle.
Pattern Formation
The development of a multicellular organism's spatial organization, the arrangement of organs and tissues in their characteristic places in three-dimensional space.
Positional Information
Molecular cues that control pattern formation in an animal or plant embryonic structure by indicating a cell's location relative to the organism's body axes. These cues elicit a response by genes that regulate development.
KNOTTED-1 gene
important in development of leaf morphology, if overexpressed it causes super compound leaves
needed for appropriate root hair distribution, if turned off root hairs develop
Reporter Gene
used to determine whether inserted gene is "turned on" since it can sometimes be difficult to tell, detectable in phenotype when product present indicates that adjacent gene is functioning (ex. luciferase causing bioluminessence in mouse embryos & tobacco plants), a genetic marker.
Phase Changes
the morphological changes that arise from transitions in shoot apical meristem activity
Meristem Identity Genes
Plant genes that promote the switch from vegetative growth to flowering.
Organ Identity Genes
Plant homeotic genes that use positional information to determine(by doing for transcription factors) which emerging leaves develop into which types of floral organs.
ABC Model
A model of flower formation identifying three classes of organ identity genes that direct formation of the four types of floral organs.
Strands which form a transvers sheet of sytoplasm, Splits the cell in plane where it will finally divide. contains mircotubes and actin filaments
Jan Baptista van Helmont
1643 "Willow tree experiment" studied plant growth by weighing a small tree, some soil, and a pot, then he planted he small tree in the dirt in the pot and water the tree regulary, after several years he removed the tre and reweighd, he concluded that plants only need water to growz(FALSE), CO2
Stephen Hales
Suggested that conserving green plants preserved rainfall. His ideas were put into practice in 1974 on the Caribbean island of Tobago, where about 20% of the land was marked as 'reserved in wood for rains' (1) FAlSE CO2
Mineral Nutrients
An essential chemical element absorbed from the soil in the form of inorganic ions.
Essential element
In plants, a chemical element that is required for the plant to grow from a seed and complete the life cycle, producing another generation of seeds.
Process by which plants that release water into the atmosphere from small pores on their leaves known as stomata., makes plants lose 90% of water weight.t
Hydroponic Culture
A method in which plants are grown without soil by using mineral solutions.
Carbon, oxygen, hydrogen, nitrogen, sulfur, phosphorous which are necessary for building and maintaining body tissues and providing energy for daily activities
Chemical elements that organisms need in small or even trace amounts to live, grow, or reproduce. Examples are sodium, zinc, copper, chlorine, and iodine. Compare macronutrients. Fuction mainly as cofactors
An abnormally yellow color of plant tissue, resulting from partial failure to develop chlorophyll, caused by a nutrient deficiency
through weathering soil will form a series of horizontal layers known as what?
A Horizon
This layer(horizon) of soil is made up of topsoil, crumbly, dark brown soil that is a mixture of humus, clay and other minerals.
B Horizon
Middle layer in a soil profile, less evolved soil, lighter in color, less life, less weathering than A horizon and above C Horizion
C Horizon
bottom layer, least evolved layer, contains minerals leached from B hor., MOSTLY contains partly weathered rock and solid rock at the bottom, is the PARENT material for the upper horizions.
Rich, dark organic material formed by decay of vegetable matter(by the action of bacteria and fungi), essential to soil's fertility because it prevents it from clumping together which allows for adequate aeration of roots and absorption of water.
Negative ions (anions)
These types of ions( like Nitrate(NO3-), phosphate(H2PO4-) are NOT bound tightly to the negatively charged soil particles and are therefore easily released and are more available to roots EXCEPT during extensive water runoff
Positive Ions (cations)
These types of ions (like K+, Na+) ARE bound tightly to the negatively charged soil particles, and are NOT likely to be leached during extensive water runoff, They become aviable for absorption by a root only after being displaced by H+ (cation exchange)
Cation Exchange
A process in which positively charged minerals are made available to a plant when hydrogen ions (secreted by a root hairs and cellular respiration) which then releases CO2 into the soil solution where it will react with H2O to form carbonic acid, and its dissociation adds H+ which displaces mineral ions from the clay particles.
N-P-K Ratio
The Fertlizer Ratio used which contains (Nitrogen, Phosphorous, and Potassium)
Drip Irrigation
A process by which precisely controlled amounts of water drip directly onto plants from pipes, thus preserving precious water resources in dry areas
The process by which wind, water, ice, or gravity transports soil and sediment from one location to another
Sustainable Agriculture
Farming methods that preserve long-term productivity of land and minimize pollution, typically by rotating soil- restoring crops with cash crops and reducing in-puts of fertilizer and pesticides.
Contour Tillage
A way of planting that is planted going around anr round instead of up and down.
An emerging nondestructive technology that seeks to cheaply reclaim contaminated areas by taking advantage of the remarkable ability of some plant species(like alpine pennycress) to extract heavy metals and other pollutants from the soil and to concentrate them in easily harvested portions of the plant.
Cell Differentiation
The structural and functional divergence of cells as they become specialized during a multicellular organism's development; dependent on the control of gene expression.
Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspring. Because of its phosphate group it is tightly bound to 4 positively charged Histones(8 total) to form a nucleosome.
Histone Code Hypothesis
This hypothesis proposes that specific combinations of modifications, rather than the overall level of histone acetylation, determine chromatin configuration
The proteins called ____ that are responsible for the first level of DNA packing in chromatin . Its mass is approximately equal to that of DNA, and it largely consists of positive amino acids(arginine, lysine), its apparent conservation in Eukaryotic genomes signals its importance. 4 of these(H2A, H2B, H3, H4) (8 total)along with DNA form a nucleosome.
Basic structural unit of chromatin; core of four types of histone ( H2A, H2B, H3, H4)(2 of each) wrapped in DNA, and prevalent during Interphase, also called beads on a string, they are linked together by linker DNA, some parts are tightly condensed(Telomeres and Centromeres), 10nm.
Looped Domains
After nucleosomes condense and link the 30 nm fiber gathers into thick supercoiled loops (80-100 nm). Tethered to protein scaffold of the (nuclear matrix)- regulates degree of supercoiling. Seen during Prophase, can become 300 nm
Densely staining condensed chromosomal regions, believed to be for the most part genetically inert, because transcription enzymes can't reach it. Darkly stained throughout the cell cycle. Usually consists of Telomeres and Centromeres
DNA that is loosely packed around histones. This DNA is more accessible to enzymes and the genes in euchromatin can be activated if needed. (True Chromatin)
Organisms made up of one or more cells that have a nucleus and membrane-bound organelles.
Differential Gene Expression
The expression of different sets of genes by cells with the same genome. Typically only about 20% of genes are expressed, however in highly differentiated cells(like muscle) even less is expressed.
Linker DNA
The string between beads of DNA on histones. They are also wrapped around a single histone, called linker histone (H1) - may not really have to know..
Nuclear Lamina
A netlike array of protein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope
A period between two mitotic or meiotic divisions during which the cell grows, copies its DNA, and synthesizes proteins
The 2nd stage in mitosis or meiosis in which the duplicated chromosomes line up along the equatorial plate of the spindle
N Terminus
the beginning of an amino acid chain, identified by a free amino group, in the histones it protrudes outwards from the nucleosome, which are sometimes modified by the addition or removal of chemicals( acetylation, methylation)
Maintain sister chromatid cohesion prior to the anaphase stage. Site of kinetochore formation. Hence, they mediate chromosome migration during the anaphase stage. This process is essential to the separation of chromatids and thus the fidelity of chromosome distribution during cell division. (Few mistakes).
First and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
regions of cytoplasmic material that in animal cells contain structures called centrioles
Central Vacoule
large fluid vacuoles found olny in plants that support pressure of fluid against the cell wall which helps the cell stand upright
2 %
The percentage of DNA that actually codes for protein.
Gene Expression
The process whereby genetic information flows from genes to proteins; the flow of genetic information from the genotype to the phenotype, usually regulated at the transcription leve;.
Histone Acetylation
the attachment of acetyl groups (-COCH3) to certain amino acids(lysine, arginine) of histone proteins at the N Terminus, this neutralizes the positive charges(so less binding to necolosomes, the chromatin becomes less compact, and the DNA is more accessible for transcription
Histone Methylation
The addition of methyl groups (-CH3) to histone tails(N Terminus), promotes condensation of the chromatin and in effect discourages (discourages transcription)
DNA Methylation
The addition of methyl groups (—CH3) to bases of DNA after DNA synthesis(DIFFERENT from Histone Methylation); may serve as a long-term control of gene expression. Serves to limit expression, may act with other enzymes to recriut deacetylation enzymes, thus giving dual repression.
Genomic Imprinting
Phenomenon in which expression of an allele in offspring depends on whether the allele is inherited from the male or female parent., related to DNA methylation
Epigenetic Inheritance
inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence of a genome, like DNA methylation, and histone methylation or acetylation
Transcription Initiation Complex
The completed assembly of transcription factors and RNA polymerase bound to a promoter. Assembled on the promoter sequende at the upstream end of the gene.
RNA Polymerase 2
In the nucleoplasm and makes a pre -mRNA and some snRNAs. snRNA's function in splicing out the introns. Part of the "Snurp's". Only one strand of DNA is used in transcription.
Control Elements
Segments of noncoding DNA that help regulate transcription of a gene by binding proteins called transcription factors.
Transcription Factors
collection of proteins that mediate the binding of RNA polymerase and the initiation of transcription
Proximal Control Elements
Control elements located close to the promoter
Still do the same job of binding proteins to DNA so that transcription can take place
Increase rate of transcription
Distal Control Elements
(groups are called enhancers), can be far away (downstream) from gene or even located in an intron.
the more distance distal control elements, groups of which are called ________, may be thousands of nucleotides upstream or downstream of a gene or even within an intron
A transcription factor that binds to an enhancer and stimulates transcription of a gene.
Mediator Proteins
Additional transcription factors that interact with proteins at the promoter to assemble the initiation complex
some specific transcription factors function as _________ to inhibit expression of a particular gene, can block the binding of activators to their control elements, or they can bind to their own control elements in an enhancer.
The recruitment of proteins by repressors that act to deacetylate histones leading to reduced transcription. Recruitment of mediator proteins is the most common mechanism for repression in Eukaryotes.
Alternative RNA Splicing
a type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns
Poly A Tail
The modified end of the 3' end (adenine base pairs) of an mRNA molecule consisting of the addition of some 50 to 250 adenine nucleotides., mRNA degradation typically begins with shortening of this.
mRNA Degradation
In multicellular eukaryotes last hours, days or weeks; duration dictates the number of protein translated from them. Breakdown starts with enzymatic shortening of poly-A tail; triggers the removal of 5' cap by enzymes, followed by the consumption by of mRNA by nucleases.
Untranslated region; part of mature mRNA; not translated; upstream of start or downstream of stop, technically an exon, Neucleotide sequences at the 3` end of this molecule are thought to help determine the lifespan length of mRNA.
Small single-strand RNA molecules that bind to mRNA molecules to block certain parts' expression. They are formed from longer RNA procurers that fold back on itself forming a long hairpin structure held together by hydrogen bonds.
Enzyme that cleaves and processes double stranded RNA to produce siRNAs or miRNAs that are 21-25 nucleotids in length
RNA Interference
technique to silence the expression of selected genes in nonmammalian organisms; uses synthetic double-stranded RNA molecules matching the sequence of a particular gene to trigger the breakdown of the gene's messenger RNA. done by (RNAi) due to siRNA.
Global Control
the simultaneous regulation of numerous genes which is a form of transcriptional regulation, which involves the activation or inactivation of one or more protein factors(MRNA), Like in fertilization the activation of a protein factor initiates a burst of synthesis.
Human Genome Project
An international effort to map the complete human genetic code. This effort was essentially completed in 2001, though analysis is ongoing.
a fibrous scleroprotein that occurs in the outer layer of the skin(epidermis) and in horny tissues such as hair feathers nails and hooves, lead to the revison of the one gene- one enzyme hypothesis.
Neurospora crassa
studied by Beadle and Tatum using X-Ray , a common bread mold that grows on a very simple medium containing sugar and simple inorganic salts
Gene Expression
the process by which DNA directs the synthesis of proteins, Has two stages transcription and translation.
the synthesis of RNA on a DNA template, the information is copied from one molecule to another, resulting in a faithful copy the gene's protein coding genes(mRNA), occurs in the NUCLEUS.
the process whereby genetic information coded in messenger RNA directs the formation of a specific polypeptide at a ribosome in the CYTOPLASM
Archibald Garrod
The first to suggest that genes dictate phenotypes through enzymes that catalyze specific chemical reactions in the cell., Reported Alkaptonuria as the first human example of what is now known as Mendelian inheritance.
A growth hormone that causes a wide variety of effects. One role is to stimulate growth of stems by promoting cell division. Farmers use it to make fruit grow larger.
Defect in homogentisate oxidase, resulting in accumulation of homogentisic acid (Alkapton) which results in black urine, and Polymerized forms results in damage to joints, calfications in CV and UT, red skin
George Beadle
Man who hypothesis that each of the various mutations affecting eye color in Drosophila blocks pigment synthesis at a specific step by preventing production of the enzyme that catalyzes that step
Along with Tatum he mutated bread mold (Neurospora Crassa) using x-rays and observed difference in food requirements by providing different enzymes at differnt steps in the catabolic pathway and discovered that each class was blocked at different steps in the pathway because mutations in the class lacked the enzyme that catalyzes the blocked step this lead to the one gne one enzyme hypothesis - which then lead to the one gene one polypedptide hypothesis
One gene One polypeptide hypothesis
The hypothesis that every gene directs the synthesis of a particular polypeptide chain; originally called the one geneone enzyme hypothesis.
Minimal medium
a defined medium that contains the minimal ingredients needed by genetically normal (wild type) strains of a particular species.
Complete Growth Medium
This is a minimal medium that is supplemented with all 20 amino acids and a few other nutrients, usually required by the mutated species.
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
A polymer (chain) of many amino acids linked together by peptide bonds.
Messenger RNA
RNA that copies the coded message from DNA in the nucleus and carries to the protein synthesizing machinery of a cell into the cytoplasm
A cell organelle constructed in the nucleolus and functioning as the site of protein synthesis in the cytoplasm; consists of rRNA and protein molecules, which make up two subunits, act as the sites of translation, and facilitate the orderly linking of amino acids into polypeptides.
Because bacteria lack _____, their DNA is not segregrated from ribosomes and the other protein synthesizing equipment.
pre- mRNA
Precursor mRNA; the first strand of mRNA produced by the gene transcription that contains both introns and exons
RNA processing
Modification of RNA transcripts(pre mRNA), including splicing out of introns, joining together of exons, and alteration of the 5' and 3' ends
Primary Transcript
in eukaryotes, the initial RNA product containing introns and exons produced by transcription of DNA; must be processed to form proteins
The Central Dogma
1. DNA is the genetic material, containing the genes that are responsible for the physical traits (phenotye) observed in all living organisms
2. DNA is replicated from existing DNA to produce new genomes
3. RNA is produced by reading DNA in a process called transcription
4. this RNA serves as the message used to decode and transmit the genetic information and synthesize proteins according to the encoded information. This process of protein synthesis is called translation.
The amount of possible base code words( 4 ^3), enough to code for the 20 amino acids known. 61 code for things while 3 are either start or stop codons.
Triplet Code
A set of three-nucleotide-long words that specify the amino acids for polypeptide chains.
Template Strand
the DNA strand that provides the pattern, or template, for ordering the sequence of nucleotides in an RNA transcript using DNA Polymerase.
Complementary Strand
A newly synthesized strand of RNA or DNA that has a base sequence complementary to that of the template strand
A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code. Written in 5` to 3` direction.
Marshall Nirenberg
made poly-U mRNA (UUUUU); when mixed with amino acids, ribosomes, & proper enzymes, a polypeptide containing only one amino acid (phenylalanine)(AAA) was produced
Start codon for protein synthesis(METHIONINE)
Repetition of messages to reduce the probability of errors in transmission, found in mRNA base sequences
Reading Frame
the way in which a cell's mRNA-translating machinery groups the mRNA nucleotides into codons.
RNA Polymerase
Enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription, can only assemble in 5` to 3` ends.
a nucleotide sequence on a DNA molecule to which an RNA polymerase molecule binds, which initiates the transcription of a specific gene, upstream from the terminator, determines which DNA strand is used as the template.
A special sequence of nucleotides in DNA that marks the end of a gene. It signals RNA polymerase to release the newly made RNA molecule, which then departs from the gene
Transcription Unit
unit, a region of a DNA molecule that is transcribed into an RNA molecule
RNA Pol 2
In Eukaryotes it is the RNA polymerase that transcribes DNA template strand when signaled by promoter
the first phase of transcription; RNA polymerase binds to DNA @ the promoter, and unwinds the double helix
2nd stage where amino acids brought by tRNAs are joined together by the ribosome in the order determined by the mRNA
The last stage of trranscription, stop of mRNA synthesis (i.e., transcription) at the terminator site, in Eukaryotes it involves the use of a polyadenton sequence.
Transcription Factors
to initiate transcription, eukaryotic RNA polymerase requires the assistance of proteins called _________ _________, which usually contains a TATA box
A DNA sequence in eukaryotic promoters crucial in forming the transcription initiation complex
Transcription Initiation Complex
the completed assembly of transcription factors and RNA polymerase bound to the promoter
last step of splicing, adds poly-a to the tail with the AUAAA code with poly-A-polymerase, then 10 to 35 nucletides the pre-mRNA is released
The 5` Cap
Contains a modified inverted nucleotide (7-methyl guanosine) which confers stability against nucleases and provides a mechanism to be recognized by the translation machinery. elps protect the pre mRNA from hydrolytic enzymes, and facilitate the export of mature mRNA from the nucleus.
Poly A Tail
The modified end of the 3' end of an mRNA molecule consisting of the addition of some 50 to 250 adenine nucleotides. Helps protect the pre mRNA from hydrolytic enzymes, and facilitate the export of mature mRNA from the nucleus.
Untranslated regions at the 5 and 3 primed ends; are part of the mRNA that will not be translated into protein but promote ribosome binding
RNA Splicing
the removal of introns and joining of exons in eukaryotic RNA, forming an mRNA molecule with a continuous coding sequence; occurs before mRNA leaves the nucleus.
a non-coding, intervening sequence within a eukaryotic gene removed during RNA splicing
A coding region of a eukaryotic gene. Exons, which are expressed except for the UTR, are separated from each other by introns.
Small Nuclear Ribonucleoproteins
(snRNPs) recognize splice sites; are composed of RNA, protein molecules at the end of introns, they are located in the cell nucleus, the RNA within it is called a (snRNA) or small nuclear RNA, forms part of spliceosomes
short for small nuclear RNA and found within snRNPs. It can remove introns during the process: RNA splicing
A spliceosome is a complex of specialized RNA (snRNPs) and protein subunits that removes introns from a transcribed pre-mRNA (segment. This process is generally referred to as splicing.
An RNA molecule that functions as an enzyme, catalyzing reactions during RNA splicing
A type of protists called ciliates; small, unicellular organisms that can be found in pond water, and object of self splicing rRNA
Alternative RNA splicing
a type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns, also explains why humans can get along with a relatively small amount of genes.
discrete structural and functional regions of proteins
Exon shuffling
the presence of introns in a gene may facilitate the evolution of new and potentially useful proteins as a result of a process known as _______ _________, by increasing the probability of a crossover (like recombinant DNA by increasing distances between exons)
Transfer RNA
Short-chain RNA molecules (L Shaped) present in the cell (in at least 20 varieties, each variety capable of combining with a specific amino acid) that attach the correct amino acid to the protein chain that is being synthesized at the ribosome of the cell, at 3` end it has amino acid.
A sequence of three bases of a tRNA molecule that pairs with the complementary three-nucleotide codon of an mRNA molecule during protein synthesis.
aminoacyl- tRNA synthetase
Enzyme which joins amino acids to the correct tRNA
Aminoacyl tRNA
A tRNA with an amino acid attached. This is made by an animoacyl-tRNA synthetase specific to the amino acid being attache.d
A violation of the base-pairing rules in that the third nucleotide (5' end) of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3' end) of a codon.
Ribosomal RNA
The MOST abundant type of RNA, which together with proteins, forms the structure of ribosomes. Ribosomes coordinate the sequential coupling of tRNA molecules to mRNA codons. Made in the nucleolus
The organelle where ribosomes are made, synthesized and partially assembled, located in the nucleus
An antibiotic produced by the actinomycete Streptomyces griseus and used to treat tuberculosis, works because of the differential sizes of rRNA in bacteria and humans.
an antibiotic (trade name Achromycin) derived from microorganisms of the genus Streptomyces and used broadly to treat infections,orks because of the differential sizes of rRNA in bacteria and humans.
P Site
one of a ribosome's three binding sites for tRNA during translation. It holds the tRNA carrying the growing polypeptide chain.
A Site
One of a ribosome's three binding sites for tRNA during translation. This site in the ribosome holds the tRNA carrying the next amino acid to be added to the polypeptide chain.
E Site
One of a ribosome's three binding sites for tRNA during translation. This site is the place where discharged tRNAs leave the ribosome.
A nucleotide composed of guanine, ribose, and three linked phosphate groups. It is incorporated into the growing RNA chain during synthesis of RNA and used as a source of energy during synthesis of proteins
N Terminus
The amino end of the methionine(START) in an RNA. The amino end
C Terminus
The end of a polypeptide chain that contains the last amino acid to be incorporated during mRNA translation; usually retains a free carboxyl group
Initiation Factors
proteins that bind to ribosomal subunits and mRNA that bring components together in the correct positions to start translation
Elongation Factors
One of a group of nonribosomal proteins required for continued translation of mRNA (protein synthesis) following initiation
Two molecules of _______ are required for Codon recognition, and it also increases the accuracy and efficency, one more _____ is hydrolyzed to provide energy fro the translocation step.
Release Factor
A cytoplasmic protein that binds to a stop codon where it appears in the A-site of the ribosome. modify the peptidyl transferase activity of the ribosome, so that a water molecule is added to the end of the completed protein. This releases the finished protein from the final tRNA, and allows the ribosome subunits and mRNA to disassociate.
Found in eukaryotic and prokaryotic cells, enable a cell to make many copies of a polypeptide very quickly during translation; multiple ribosomes attached to an MRNA strand
Post Translation Modification
occurs mainly in Golgi
includes addition of sugars, lipids, etc. to complete polypeptide
also have polypeptides that are cleaved or several different polypeptides that come together to form final protein
(ex.- hemoglobin)
Primary Structure
The first level of protein structure; the specific sequence of amino acids making up a polypeptide chain.
Secondary Structure
The localized, repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bond formation between constituents of the backbone.Alpha helices and beta pleated sheets describe this
Quaternary Structure
The fourth level of protein structure; the complex shape resulting from the association and aggregation of two or more polypeptide subunits.
Tertiary Structure
Irregular contortions of a protein molecule due to interactions of side chains involved in hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges. (Making Up the 3-D Structure)
Free Ribosomes
ribosomes that float in the cytosol to make the proteins that are used there
Bound Ribosomes
ribosomes that are attached to the endoplasmic reticulum to make proteins to be exported, to be embedded in membranes, and to be shipped elsewhere within the cell
Carboxyl Group
A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group.
Carbonyl Group
an organic molecule, a functional group consisting of a carbon atom linked to a double bond to an oxygen atom, C=O
Amino Group
A functional group that consists of a nitrogen atom bonded to two hydrogen atoms; can act as a base in solution, accepting a hydrogen ion and acquiring a charge of +1., -NH2
Thiol Group
Phosphate Group
A chemical group consisting of a phosphorus atom covalently bonded to four oxygen atoms; important in energy transfer., , -OPO3^-2; contributes neg charge to molecule of which it is a part ; has potential to react with water releasing NRG
Hydroxyl Group
A functional group consisting of a hydrogen atom joined to an oxygen atom by a polar covalent bond. Molecules possessing this group are soluble in water and are called alcohols.
Signal Peptide
A sequence of about 20 amino acids at or near the leading (amino) end of a polypeptide that targets it to the endoplasmic reticulum or other organelles in a eukaryotic cell.
Signal Recognition Particle
(SRP), a protein-RNA complex that recognizes a signal peptide as it emerges from a ribosome and helps direct the ribosome to the endoplasmic reticulum (ER) by binding to a receptor protein on the ER
During protein synthesis, the third stage in the elongation cycle when the RNA carrying the growing polypeptide moves from the A site to the P site on the ribosome
small nucleolar RNA that form snoRNPs that modify rRNA and other snRNAs
class of double-stranded RNAs about 23 nucleotides in length that silence gene expression; act by either promoting the degradation of mRNAs with precisely complementary sequences or by inhibiting the transcription of genes containing precisely complementary sequences, also called small interfering RNA
(microRNA) about 20 nucleotides long, a small, single-stranded RNA molecule, generated from a hairpin structure on a precursor RNA transcribed from a particular gene, it associates with one or more proteins in a complex that can degrade or prevent translation of an mRNA with a complementary sequence, up to 1/3 of all human genes may be regulated by ______
Random errors in gene replication that lead to a change in the sequence of nucleotides; the source of all genetic diversity
Point Mutation
mutation that affects a single nucleotide, usually by substituting one nucleotide for another
Base Pair Substitution
A type of point mutation; the replacement of one nucleotide and its partner in the complementary DNA strand by another pair of nucleotides. Some are called silent mutations
Missense Mutation
A point mutation in which a codon that specifies an amino acid is mutated into a codon that specifies a different amino acid.
Nonsense Mutation
A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.
A mutation involving the addition of one or more nucleotide pairs to a gene.
a nucleotide is deleted, which changes the amino acid sequence.
Frameshift Mutation
A mutation occurring when the number of nucleotides inserted or deleted is not a multiple of three, resulting in the improper grouping of the following nucleotides into codons.
agents, such as chemicals or radiation, that damage or alter genetic material in cells
This tumor suppressor gene causes cell cycle arrest in G1, providing time for DNA repair. If repair is successful, cells re-enter the cycle. If unsuccessful, apoptosis
proto oncogenes
normal cellular genes that are important regulators of normal cellular processes, they promote growth. alterations in the expression of these cells resulr in oncogenes
Silent Mutation
A point mutation in which a codon that specifies an amino acid is mutated into a new codon that specifies the same amion acid.
Spontaneous Mutations
Natural changes in the DNA caused by unidentified environmental factors
Hermann Muller
Scientist(s) who demonstrated that mutations and hereditary changes can be caused via radiation.
research on tumor viruses led to the discovery of cancer-causing genes called ___________ in certain retroviruses
An RNA virus that reproduces by transcribing its RNA into DNA and then inserting the DNA into a cellular chromosome; an important class of cancer-causing viruses.
A _______ is a region of DNA whose final product is either a polypeptide or an RNA molecule.
Sickle Cell Disease
A human genetic disease caused by a recessive allele that results in the substitution of a single amino acid in the hemoglobin protein; characterized by deformed red blood cells that can lead to numerous symptoms.
____________________ are bacterial viruses with a polyhedral head and a helical tail, that also eat bacteria.
Rosalind Franklin
a British scientist that studied the DNA molecule using a technique called x-ray diffraction and was able to decipher important clues about its structures
deoxyribonucleic acid; the genetic material that carries information about an organism that is passed from parent to offspring AND is used by an individual as the recipe for making proteins
Hershey and Chase
Used radioactive material to label DNA(P-32) and protein (S -35), then used a blender to separate the phage(T2) from the bacteria(E-Coli), and centrifuged the mixture so that bacteria at bottom formed a pellet, and when analyzed measured the radioactivity in the pellet and liquid(supernatant). ; infected bacteria passed on DNA; helped prove that DNA is genetic material not proteins (at least for viruses)
Francis Crick
Described the Central Dogma of Gene Expression. DNA to RNA to protein, Cambridge University, works with James Watson, built model of DNA, reclusive, won nobel prize, studies chemical nature of dreams.
Oswald Avery
American Bacteriologist who inspired by Grifith's experiment (Transofrmation), had several experiments that tested if DNA was the genetic material (It Was). Technically not given credit McCarty and Macleod(did announce) but (Hershey and Chase) are usually given credit.
Nucleic Acid
an organic compound, either RNA or DNA, whose molecules are made up of one or two chains of nucleotides and carry genetic information
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
Frederick Griffith
British Medical officer who performed experiment using 2 varieties of (streptococcus pneumonia) , pathogenic/ non pathogenic, that led to discovery of DNA, concluded there was is a TRANSFORMATION from dead bacteria to live bacteria, studied the transforming substance
A change in genotype and phenotype due to the assimilation of external DNA by a cell (Coined by Griffith) . (DO not confuse with other transormation)
The conversion of a normal animal cell to a cancerous cell
James Watson
American scientist. With Francis Crick, he elucidated the structure and function of the DNA double helix. He shared the 1962 Nobel Prize in physiology or medicine with Crick and Maurice Wilkins. He served as the head of the Human Genome Research program from 1989 to 1992.
worked with Avery and Mcleod, they discovered that DNA is what makes chromosomes and genes
Bacteriophage consisting of only DNA and protein. Replicates by invading bacteria(like E- Coli) and using its cellular components to produce progeny. Used in hershey and Chases expiriments.
The liquid on top of material deposited by settling or centrifugation.
Erwin Chagraff
Analyzed the base composition of DNA and saw that it varied from species to species(shows the diversity of species).He also found that the amount of A nucleotides approximately equaled the number of T nucleotides, and the number of C nucleotides approximately equaled the number of G nucleotides. . this became known as Chagraff's rule.
Chagraff's rule.
A rule that thymine combines w/ adenine in equal amounts;and cytosine combines w/ guanine in equal amounts.
Nitrogenous bases that have a single ring of carbon and nitrogen atoms, such as cytosine and thymine
Nitrogeneous bases that have a double ring of carbon and nitrogen atoms such as adenine and guanine
X- Ray Crystallography
A technique that depends on the diffraction of an X-ray beam by the individual atoms of a crystallized molecule to study the three-dimensional structure of the molecule. Helped Watson figure out the double helix of DNA
Double Helix
Shape of a DNA molecule formed when two twisted DNA strands are coiled into a springlike structure and held together by hydrogen bonds between the bases
Watson- Crick Model
DNA consists of two nucleotide strands; strands run in opposite directions 5'=>3' and 3'=>5' (think of 2 magnets together). Strands held together by hydrogen bonds between bases. A binds with T with 2 hydrogen bonds and C with G with three hydrogen bonds. Molecule is a double helix
Semiconservative Model
Type of DNA replication in which the replicated double helix consists of one old strand, derived from the old molecule, and one newly made strand. (RIGHT). Tested by Matheson and Stahl
Conservative Model
A model based on the hypothesis that when a double helix replicates, the parent strands come back together and there is a completely new daughter strand. (WRONG) Tested by Matheson and Stahl
Dispersive Model
Model that says each strand of both daughter molecules contains a mixture of old and newly synthesized DNA (WRONG) Tested by Matheson and Stahl using istopes of Nitrogen
There are one in _____________ nucleotide base pairs per replication.
Origins of Replication
Sites where the replication of a DNA molecule begins, is where two parental strands separate and form replication bubbles, which expand laterally in both directions. There may be thousands of these in a eukaryote' s DNA.
Replication Bubble
The region where two replication forks are in close proximity to eachother, producing a bubble in the replicating DNA
Replication fork
a Y-shaped point that results when the two strands of a DNA double helix separate so that the DNA molecule can be replicated
DNA Polymerases
An enzyme that catalyzes the elongation of new DNA at a replication fork by the addition of nucleotides(Nucleoside triphosphate ) to the existing chain at and ONLY at the 3` end.
Nucleoside triphosphate
Molecule consisting of a nitrogenous base, a pentose sugar, and three phosphate groups, e.g., adenosine triphosphate (ATP) only difference is in the sugar(deoxirbose) compared with ribose. Is what is actually added to a growing neuclotide strand by DNA Polymerase
The triphosphate monomers are chemically reactive because their triphosphate tails (-OPO3-) are ____________
when each monomer of dATP joins DNA strand it looses two phosphate groups creating this molecule, and drives the polymerization of DNA.
Parallel, but running in opposite directions. The 5' end of one strand of DNA aligns with the 3' end of the other strand in a double-helix.
DNA Pol 3
Using parental DNA as a template, synthesizes new DNA strand by covalentley adding nucleotides to the 3' end of a pre-existing DNA strand or RNA primer(leading strand). Always makes the new strand 5' to 3'., The Okazaki Fragments are added(after lagging) in the 5' to 3'
Okazaki Fragments
A short segment of DNA synthesized away from the replication fork on a template strand during DNA replication, many of which are joined together to make up the lagging strand of newly synthesized DNA
Lagging Strand
The newly forming daughter strand of DNA that is replicated in a discontinuous fashion, via Okazaki fragments that will ultimately be ligated together; the daugther strand that is replicated in the opposite direction that parallel DNA is unwinding
Leading Strand
The new continuous complementary DNA strand synthesized along the template strand in the mandatory 5' 3' direction by DNA Pol 3 .
An enzyme that connects two fragments of DNA (their sugar phosphate backbones) to make a single fragment; also called DNA _____. This enzyme is used during DNA replication and is also used in recombinant DNA research.
Recombinant DNA
DNA in which one or more segments or genes have been inserted, either naturally or by laboratory manipulation, from a different molecule or from another part of the same molecule, resulting in a new genetic combination.
An already existing RNA chain bound to template DNA to which DNA nucleotides are first added during DNA synthesis.
An enzyme that joins RNA nucleotides to make the primer using the parental DNA strand as a template.
DNA Pol 1
repairs and patches DNA (5-3 exonuclease activity= clears away short stretched of nucleotides SEVERAL at a time); removes RNA primer as replication forks move and replaces them with DNA.
an enzyme that untwists the double helix at the replication forks, separating the two parental strands and making them available as template strands, after that Topoisomerase relieves the strain caused by the untwisting.
A protein that breaks, swivels, and rejoins DNA strands. During DNA replication, topoisomerase helps to relieve strain in the double helix ahead of the replication fork.
Single Strand binding Protein
A protein that binds to the unpaired DNA strands during DNA replication, stabilizing them and holding them apart while they serve as templates for the synthesis of complementary strands of DNA.
Mismatch Repair
The cellular process that uses specific enzymes to remove and replace incorrectly paired nucleotides, a heridiatary defect in one of them is associated with colon cancer.
An enzyme that cuts DNA or RNA, either removing one or a few bases or hydrolyzing the DNA or RNA completely into its component nucleotides., after it does this the resulting gap is filled in by DNA Pol 1 and ligase which add and cement new nucleotides.
Nucleotide Excision Repair
Enzymes detect damaged DNA, nuclease enzymes cut out the damaged area, DNA polymerase adds nucleotides, ligase completes process by closing the break in the sugar-phosphate backbone
Thymine Dimer
Abnormally chemcally bonded thymine bases in DNA resulting from ultra violet irradion damage. the cellular processes that repair often make errors that cause mutations
Xeroderma Pigmentosum
An Autosomal recessive disease , caused by a defect in the nucleotide excision repair system; Accumulation of damaged DNA; Risk of cancer, a rare genetic condition characterized by an eruption of exposed skin occurring in childhood and photosensitivity with severe sunburn (Mainly from UV )
Prokaryotes do not have a problem with completing the 5` end of daughter strands, because their DNA is ___________
The protective structure at each end of a eukaryotic chromosome. Specifically, the tandemly repetitive DNA at the end of the chromosome's DNA molecule. (TTACGG) in humans, protects the DNA from being eroded ater succesive DNA replications, and somehow activate with other proteins to make sure that the staggered end of the daughter molecule do not activate the cell systems defense for monitoring DNA damage.
The six nucleotide sequence of human teleomeres is __________
An enzyme that catalyzes the lengthening of telomeres. The enzyme includes a molecule of RNA that serves as a template for new telomere segments. Is not active in most cells but is in most of the germ cells which help result in the maximization length of a zygote
Germ Cell
The cell that undergoes meiosis (in humans, only found in the ovaries and testes)
Meselson and Stahl
Proved that DNA replicates in a semiconservative fashion, confirming Watson and Crick's hypothesis. Cultured bacteria in a medium containing heavy nitrogen (15N) and then a medium containing light nitrogen (14N); after extracting the DNA, they demonstrated that the replicated DNA consisted of one heavy strand and one light strand
the science which deals with the formation, structure, and function of cells
Chromosome Theory of Inheritance
A basic principle in biology stating that genes are located on chromosomes and that the behavior of chromosomes during meiosis accounts for inheritance patterns.
Anaphase 1
The third phase of Meiosis where homologus pairs seperate and move to opposite poles
Thomas Hunt Morgan
Dicovered that sometimes alleles for different traits do not assort independently and can be linked because they exist on the same chromosome. Discovered that sex-linked traits appear in different rates in males and in females because males need only one recessive allele to express the recessive trait.
Wild Type
An individual with the phenotype most commonly observed in natural populations; also refers to the phenotype itself. +
Mutant Phenotypes
traits that are alternatives to the wild type are called ________ _____ because they are due to alleles assumed to have originated as changes (mutations) of the wild-type allele
The physical traits that appear in an individual as a result of its gentic make up.
the particular alleles at specified loci present in an organism
Linked Genes
genes located on the same chromosome that tend to be inherited together in genetic crosses, when following these genes they will deviate from the law of independent assortment
Law of independent assortment
Mendel's second law, stating that each allele pair segregates independently during gamete formation; applies when genes for two characteristics are located on different pairs of homologous chromosomes.
Genetic Recombination
new combination of genetic information in a gamete as a result of crossing over during prophase I of meiosis
Parental Types
Offspring with a phenotype that matches one of the parental phenotypes.
Recombinant Types
Offspring who have inherited new combinations of genes and have phenotypes that don't match either parental phenotypes (usually 50%)
Crossing Over
the exchange of genetic material between homologous chromosomes during meiosis; can result in genetic recombination
Recombination Frequency
percentage of recombinants, meaning percentage of of offspring that had traits from crossover. recombination frequencies are lower when alleles are closer together.
Genetic Map
an ordered list of genetic loci (genes or other genetic markers) along a chromosome
Alfred Sturtevant
Constructed a gene map of the fruit fly using crossing over frequencies.
Linkage Map
A genetic map based on the frequencies of recombination between markers during crossing over of homologous chromosomes. The greater the frequency of recombination between two genetic markers, the farther apart they are assumed to be. See also genetic map.
Map Units
A measurement of the distance between genes; one map unit is equivalent to a 1 percent recombination frequency. Can be a maximun vaalue of 50%
Cytogenetic Maps
a chart of a chromosome that locates genes with respect to chromosomal features distinguishable in a microscope, by comparing this with a linkage map we can determine that the linear order is the same but the spacing between genes is not.
X 0 System
how gender is determined in grasshoppers and cockroaches, male has one X and a female has two X's
Z W System
birds, some fishes and insects; sex determined by eggs, female has ZW and male has ZZ (ex. rooster)
Haplo- Diploid system
There are no sex chromosomes in most species of bees and ants. Females develop from fertilized eggs (diploid) and males develop from unfertilized eggs (haploid). No fathers
The gene on the Y chromosome whose product instructs the undifferentiated fetal gonads to develop into testes
Sex linked Gene
any gene that is located on a sex chromosome
Because _____ have only one locus, the term homozygous is useless(hemizygous) instead , any ____ receiving a recessive sex linked gene from the mother will inherit it.
in a diploid organism, having only one allele for a given trait, typically the case for X-linked genes in male mammals and Z-linked genes in female birds
A human genetic disease caused by a sex-linked recessive allele; characterized by excessive bleeding following injury due to an absence of the essential proteins allowed for clot formation, treated with intravenous injections of the protein.
Clot Formation
Happens when cut tissue release thromboplastin-interacts with factor VII
prothrombin--> thrombin
fibrinogen--(thrombin)--> fibrin
Barr Body
A dense object lying along the inside of the nuclear envelope in female mammalian cells, representing an inactivated X chromosome, reactivated in the cells that give rise to the ova.
Mary Lyon
who suggests that early in the development of normal females one of the X chromosomes is inactivated in every somatic cell; random as to which is expressed: in some cell the material chromosome is expressed; in other cells the male chromosome is expressed (Females consist of a mosiac of two types of cells.
The spontaneous expulsion of a baby from the mother's body before week 20 of pregnancy
X is inactive in specific transcript. Transcribed only from the inactive X. It is located in teh XIC. RNa is 17kb lond, but never leaves the nucleaus and does not code for a protein. Non-coding RNa, that coats the inactive X. Required for X activation.
error in meiosis in which homologous chromosomes don't separate; gametes end up with wrong number of chromosomes
A chromosomal aberration in which one or more chromosomes are present in extra copies or are deficient in number.
A chromosomal condition in which a particular cell has an extra copy of one chromosome, instead of the normal two; the cell is said to be _______ for that chromosome.
A chromosomal condition in which a particular cell has only one copy of a chromosome, instead of the normal two; the cell is said to be ________ for that chromosome.
A chromosomal alteration in which the organism possesses more than two complete chromosome sets.
(1) A deficiency in a chromosome resulting from the loss of a fragment through breakage. (2) A mutational loss of one or more nucleotide pairs from a gene.
An aberration in chromosome structure resulting from an error in meiosis or mutagens; duplication of a portion of a chromosome resulting from fusion with a fragment from a homologous chromosome.
An aberration in chromosome structure resulting from reattachment in a reverse orientation of a chromosomal fragment to the chromosome from which the fragment originated.
change to a chromosome in which a fragment of one chromosome attaches to a nonhomologous chromosome
a group of symptoms or signs that collectively characterize or indicate a disease, disorder, abnormality, etc.
Down Syndrome
A human genetic disease caused by presence of an extra chromosome 21; characterized by mental retardation and heart and respiratory defects. Often called Trisomy 21
Trisomy 21
condition in which an individual has three number 21 chromosomes, resulting in Down syndrome
Turner Syndrome
Chromosome disorder in females. a x chromosome is missing or part of one x is deleted. short stature and webbed neck.
Klinefelter Syndrome
syndrome in males that is characterized by small testes and long legs and enlarged breasts and reduced sperm production and mental retardation
Philadelphia Chromosome
a shortened chromosome produced when a large portion of chromosome 22 is exchanged with a small fragment from a tip of chromosome 9
What leukemia is characterized by Philadelphia chromosomal translocation (9;22); massive splenomegaly; peripheral leukocytosis (commonly > 100, 00); decreased LAP levels; and nonspecific symptoms of fatigue, malaise, weight loss, and anorexia?
Genomic Imprinting
a phenomenon in which expression of an allele in offspring depends on whether the allele is inherited from the male or female parent
the process by which certain animals form attachments during a critical period very early in life
one of the first imprinted genes to be identified. found in mice. encodes a growth hormone called insulin-like growth factor 2 that is needed for proper growth. lack of it results in dwarf.
process that plays a role in the control of genetic expression, initiation of DNA Replication, Protection against Viral infection, and Repair of DNA
Extranuclear Genes
Genes that are found in organlles in the cytoplasm; mitcohondria, chrlorplasts. Inherited maternally
Mitochondrial Myopathy
muscle weakeness, death of muscle cells, dysphagia, speech difficulties, affects muscles of eye
process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches
C4 Plants
A plant that changes CO2 into a four carbon compound before entering the Calvin cycle for photosynthesis, is related to their unique leaf anatomy( 2 distinct bundle sheath cells and looselty arranges mesophyll cells), CO2 is incorporated into the mesophyll cells and PEP Carboxylase. (Sugarcane, Corn most Grasses)
an organism that obtains energy and nutrients by feeding on other organisms or their remains.
organisms that use energy from sunlight or from chemical bonds in inorganic substances to make organic compounds, and are thefore called producers.
An organism that obtains organic food molecules by eating other organisms or their by-products, and are therefore consumers.
An organelle found only in plants and photosynthetic protists that absorbs sunlight and uses it to drive the synthesis of organic compounds from carbon dioxide and water.
a green pigment that is present in most plant cells, that gives plants their characteristic green color, and that reacts with sunlight, carbon dioxide, and water to form carbohydrates, found mainly in the cells of the mesophyll
The ground tissue of a leaf, sandwiched between the upper and lower epidermis and specialized for photosynthesis because it contains most of the chlorophyll.
A microscopic pore surrounded by guard cells in the epidermis of leaves and stems that allows gas exchange and some water vapor exchange .
The fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water. (Where Calvin Cycle takes place).
A flattened membrane sac inside the chloroplast, used to convert light energy to chemical energy
Thylakoid Space
space within each thylakoid which is thought to be connected to the space within every other thylakoid
A stacked portion of the thylakoid membrane in the chloroplast. Grana function in the light reactions of photosynthesis
Guard cells
Specialized cells in the epidermis of the leaf that control the opening and closing of stomata by responding to changes in water pressure.
A hard material embedded in the cellulose matrix of vascular plant cell walls that functions as an important adaptation for support in terrestrial species.
Van Niel
(Last name) Hypothesized that oxygen was released from water, not carbon dioxide, by using the fact that some bacteria use H2S instead of Water for photsynthesis., 20 years after scientists used a oxygen 18 as a radiotracer.
Light Reactions
The steps in photosynthesis that occur on the thylakoid membranes of the chloroplast and that convert solar energy to the chemical energy of ATP and NADPH, evolving oxygen in the process.
Calvin Cycle
Also known as the dark reactions, , The second of two major stages in photosynthesis (following the light reactions), involving atmospheric CO2 fixation and reduction of the fixed carbon into carbohydrate by addition of electrons (Occurs in the Stroma)
Nicotinamide adenine dinucleotide phosphate, an acceptor that temporarily stores energized electrons produced during the light reactions.
The process of generating ATP from ADP and phosphate by means of a proton-motive force generated by the thylakoid membrane of the chloroplast during the light reactions of photosynthesis
Melvin Calvin
American scientist who worked out the details of the Calvin cycle
Carbon Fixation
The incorporation of carbon from carbon dioxide into an organic compound by an autotrophic organism.
The distance between crests of waves, such as those of the electromagnetic spectrum.
Electromagnetic Spectrum
arrangement of electromagnetic radiation--including radio waves, visible light from the Sun, gamma rays, X rays, ultraviolet waves, infrared waves, and microwaves--according to their wavelengths
Visible Light
That portion of the electromagnetic spectrum detected as various colors by the human eye, ranging in wavelength from about 380 nm to about 750 nm.
a quantum of light; a discrete bundle of electromagnetic energy that interacts with matter similarly to particles
An instrument that measures the proportions of light of different wavelengths absorbed and transmitted by a pigment solution.
Absorption Spectrum
Graph plotting a pigment's light absorption versus wavelength
Chlorophyll a
Main photosynthetic pigment in plants, algae, and cyanobacteria. Works best with violet- blue and red light work best for it. Also is blue green.
the scientist that took algae, prism, light source, and exposed them to aerobic bacteria (which congregated near purple and red light, indicating that there's the most oxygen there, and they are therefore the best colors for photosynthesis), and green is the least effective.
An accessory pigment, either yellow or orange, in the chloroplasts of plants. By absorbing wavelengths of light that chlorophyll cannot, carotenoids broaden the spectrum of colors that can drive photosynthesis, and function in photoprotection
Chlorophyll b
A type of yellow-green accessory photosynthetic pigment that transfers energy to chlorophyll a.
C3 Plants
More then 95 % of plants on the earth are this. A plant that changes C02 into a three carbon compound (3-phosphoglycerate) before entering the Calvin cycle for photosynthesis. (Rice Wheat, Soybeans)
A process in which carotenoids absorb and dissipate exessive light energy that would otherwise damage chlorophyll or interact with oxygen forming reactive oxidative molecules that are dangerous to the cell;
in the thylakoid membranes of chloroplasts, a cluster of chlorophyll and other pigment molecules that harvest light energy for the light reactions of photosynthesis
Light Harvesting Complex
A complex of proteins associated with pigment molecules (including chlorophyll a, chlorophyll b, and carotenoids) that captures light energy and transfers it to reaction-center pigments in a photosystem.
Photosystem 1
(Functions 2nd) Reaction Center is P700(far red), Uses Light to excite electrons and converts NADP to NAPDH, It has light dependent reactions, also spilts water to make Oxygen.
Photosystem 2
(Functions 1st) Reaction Center is P680(red), a light reaction in which ATP and NADPH are formed
Reaction Center
Complex of proteins associated with two special chlorophyll a molecules and a primary electron acceptor. Located centrally in a photosystem, this complex triggers the light reactions of photosynthesis. Excited by light energy, one of the chlorophylls donates an electron to the primary electron acceptor, which passes an electron to an electron transport chain.
Primary Electron Acceptor
A specialized molecule sharing the reaction center with the pair of reaction-center chlorophyll a molecules; it accepts an electron from one of these two chlorophylls.
Noncyclic electron flow
A route of electron flow during the light reactions of photosynthesis that involves both photosystems and produces ATP, NADPH, and oxygen. The net electron flow is from water to NADP+.
Chlorophyll a molecules that serve as the reaction center of Photosystem II, transferring photoexcited electrons to a primary acceptor; named by their absorption peak at 680 nm. If missing an electron it is the strongest biological oxidizing agent knwn.
(connects 2 photosystems) small diffusable protein that receives e-'s from photosystem II and transfers to photosystem I
Transports the protons to the lumen of the thylakoid discs ,while the electrons continue through the chain into the cytochrome bf6 protein complex
an iron-containing protein, a component of electron transport chains in mitochondria and chloroplasts
in photosystem I, the chlorophyll also absorbs light, and the excited electrons are donated to _____, a small, iron/sulfur-containing protein
NADP+ reductase
enzyme that transfers a proton and two electrons from ferredoxin to NADP+, forming NADPH (2 ELECTRONS are required).
Cyclic Electron Flow
A route of electron flow during the light reactions of photosynthesis that involves only photosystem I and that produces ATP but not NADPH or oxygen. Makes up the differences in ATP required for the Calvin Cycle., and a rise in NADPH can contribute to a switch to this route.
in chloroplasts and mitochondria, a process in which the movement of protons down their concentration gradient(have to be more electronegative as you go down) across a membrane is coupled to the synthesis of ATP
ATP Synthase
large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP
Raw material from which plants and other producers assemble glucose...this molecule is a product of the calvin cycle.
Ribulose carboxylase, the enzyme that catalyzes the first step of the Calvin cycle (the addition of CO2 (carbon fixation) to RuBP, or ribulose bisphosphate). The product of the reaction is a 6 carbon intermediate( that is so unstable it immediately splits in half) forming 2 molecules of 3-phosphoglycerate. Is probably the most abundant protein on earth.
1,3 biphosphoglycerate
2nd Step of Calvin Cycle a molecule produced by the phosphorylation(taken from ATP) of 3-phosphoglycerate. Thens the electrons from NADPH reduce the carboxyl group of this to make the aldehyde group of G3P.
A metabolic pathway that consumes oxygen, releases carbon dioxide, generates no ATP, and decreases photosynthetic output; generally occurs on hot, dry, bright days, when stomata close and the oxygen concentration in the leaf exceeds that of carbon dioxide.
CAM Plants
A plant that uses crassulacean acid metabolism, an adaptation for photosynthesis in arid conditions, first discovered in the family Crassulaceae. Carbon dioxide entering open stomata during the night is converted into organic acids, which release CO2 for the Calvin cycle during the day, when stomata are closed. Different from C4 plants in that carbon fixation occur in the same place just at different times. (Pineapples, Cacti, most Succulent plants)
Bundle sheath cells
Cells in the leaves of C4 plants in which the four-carbon acids produced during carbon fixation are broken down to three-carbon acids and CO2.
PEP Carboxylase
An enzyme that adds CO2 to phosphoenolpyruvate (PEP) to form oxaloacetate in C4 plants. It acts prior to photosynthesis. It is good because it has NO affinity for oxygen (less photorespiration)
The mesophyll cells of a C4 plant export their 4 carbon compound to the bundle sheath cells through __________
An open channel in the cell wall of plants through which strands of cytosol connect from adjacent cells
Crassulacean acid Metabolism
An adaptation for photosynthesis in arid conditions, first discovered in the family Crassulaceae. In this process, a plant takes up CO2 and incorporates it into a variety of organic acids at night; during the day, CO2 is released from organic acids for use in the Calvin cycle.
The percentage of organic material that is consumed by cellular repiration during photosynthesis
the production of light by means of a chemical reaction in an organism
the sum of all chemical processes that occur in an organism, and is also an emergent property that arises from the interactions between molecules within the environment.
Metabolic Pathway
A series of chemical reactions that either builds a complex molecule (anabolic pathway) or breaks down a complex molecule into simpler compounds (catabolic pathway). In each step of the pathway an enzyme is used.
A process in which large molecules are broken down into smaller ones, for example cellular respiration.Releases energy .
A process in which large molecules are built from small molecules (Steriods), they must consume energy in order to happen.
Cellular Respiration
process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
the study of how organisms manage their energy resources
the capacity of a physical system to do work
Kinetic Energy
the mechanical energy that a body has by virtue of its motion. KE=1/2 mv squared.
Potential Energy
the mechanical energy that a body has by virtue of its position. PE =mgh
the transfer of thermal energy
Chemical Energy
that part of the energy in a substance that can be released by a chemical reaction
study of energy transformations that occur in a collection of matter
a specific portion of matter in a given region of space that has been selected for study during an experiment or observation
Everything in the universe except the system.
Open System
matter can enter from or escape to the surroundings
Closed System
A system that allows the exchange of energy, but not matter, between the system and its surroundings.
First Law of Thermodynamics
the fundamental principle of physics that the total energy of an isolated system is constant despite internal changes, also known as the principle of the conversation of energy..
Second Law of Thermodynamics
The principle stating that every energy transfer or transformation increases the entropy of the universe. Ordered forms of energy are at least partly converted to heat. Or the Entropy of the Universe is constant.
A quantitative measure of disorder or randomness, symbolized by S.
Free Energy
The portion of a system's energy that can perform work when temperature and pressure are uniform throughout the system.
J. Willard Gibbs
defined the Gibbs free energy system, deltaG
point at which the number of diffusing molecules moving in one direction is equal to the number moving in the opposite direction
Exergonic Reaction
A spontaneous chemical reaction in which there is a net release of free energy.
Endergonic Reaction
A non-spontaneous chemical reaction, in which free energy is absorbed from the surroundings.
Mechanical Work
the type of cellular work that includes the beating of cilia, the contraction of muscle cells, and the movement of chromosomes during reproduction
Transport Work
the pumping of substances across membranes against the direction of spontaneous movement
Chemical Work
the type of cellular work that includes the pushing of endergonic reactions, which would not occur spontaneously, such as the synthesis of polymers from monomers
Energy Coupling
In cellular metabolism, the use of energy released from an exergonic reaction to drive an endergonic reaction.
adenosine triphosphate, an organic molecule that acts as the main energy source for cell processes; composed of a nitrogenous base (adenine), a sugar(ribose), and three phosphate groups, the bonds betwen the phosphate groups can be broken by hydrolysis.
Referring to a molecule that has been the recipient of a phosphate group, and usually undergoes a conformational change.
a chemical process in which a compound is broken down and changed into other compounds by taking up the elements of water.
involuntary contrctions of skeletal muscles initiated when the core body temp falls below its central setpoint, resulting in an increase in heat production, started by ATP hydrolysis.
ATP Cycle
Regenerates ATP. Energy is stored in the high-energy bond extending to the last phosphate. Heat is given off when ATP breaks into ADP (adenosine diphospate) and P (phosphate). The energy released when ATP->ADP +P is transferred to endergonic reactions through coupling
an enzyme that catalyzes the hydrolysis of sucrose into glucose and fructose
Activation Energy
the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur
Transition State
An unstable grouping of atoms that exists momentarily in the course of a reaction, when a system is highest in energy.
a substance on which an enzyme acts during a chemical reaction
Enzyme Substrate Complex
a temporary complex formed when an enzyme binds to its substrate molecules
Active Site
The specific portion of an enzyme that attaches to the substrate by means of weak chemical bonds.
Induced Fit
The change in shape of the active site of an enzyme so that it binds more snugly to the substrate, induced by entry of the substrate.
the state that an enzyme is said to be in if as soon as the product of one reaction leaves, a new substrate enters the active site, the rate of product formation can only be increased by adding more enzymes.
Optimal Conditions
Because an enzyme is a protein, it is affected by pH and Temperature, and as a consequence works best in ________________ that favor the most active conformation of the enzyme molecule.
35 - 40 Celsius
Most human enzymes have a temperature from _______ _____that represents the optimal conditions for temperature. Generally a enzymatic reaction increases with increasing temperature however, past a point it will be denatured and its activity will fall rapidly. Bacteria and archaea (Thermophiles) that live in hot springs have their optimal temperature at about 70 degrees celsius.
Organisms which are adapted to high temperatures, such as in hot springs and geysers, smoker vents on the sea floor, and domestic hot water pipes.
The optimal pH values for most enzymes are____, however pepsin a digestive enzyme in the stomach works best at pH of 2.
The main protease secreted by the pancreas; trypsin is activated (from trypsinogen) by enterokinase, and subsequently activates other pancreatic enzymes. Works best at a pH of 8 (Alkaline)
A protein-digesting enzyme secreted by the chief cells of the gastric glands. Pepsin is secreted in its inactive form (pepsinogen) and is activated by gastric acid. It is unusual in that its pH optimum is around 1-2; most of these enzymes in the body function best at neutral pHs
An enzyme of the small intestine that converts trypsinogen to trypsin.
Any nonprotein molecule or ion that is required for the proper functioning of an enzyme. Cofactors can be permanently bound to the active site or may bind loosely with the substrate during catalysis (Minerals)
An organic molecule serving as a cofactor. Most vitamins function as this in important metabolic reactions
Competitive Inhibitors
A substance that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics. Can be overcome by increasing the concentration of substrate so that more active sites become available than inhibitor molecules.
Noncompetitive Inhibitors
A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing its conformation so that it no longer binds to the substrate.
A highly toxic chemical nerve agent that inhibits the activity of cholinesterase by irreversibly binding to it, so the muscles are supplied with a continous amount of calcium and remain in a state of tetanus
Irreversible anticholinesterase. Excessive stimulation of nicotinic receptors - muscle weakness and paralysis. Excessive parasympathomimetic effects - salivation, bronchoconstriction, miosis, bradycardia, increased GIT motility and tone. The potentially fatal adverse effect is paralysis of the respiratory muscles. Posioning by this drug can be treated with pralidoxime or atropine.
Any of various antibiotics obtained from penicillium molds (or produced synthetically) and used in the treatment of various infections and diseases. Works by binding to the active site of enzymes that many bacteria use to make their cell walls.
Allosteric Regulation
The binding of a regulatory molecule to a protein at one site that affects the function of the protein at a different site.
Allosteric Site
A site on an enzyme other than the active site, to which a specific substance binds, thereby changing the shape and activity of the enzyme.
A kind of allosteric regulation whereby a shape change in one subunit of a protein caused by substrate binding is transmitted to all the others, facilitating binding of subsequent substrate molecules.
Feedback Inhibition
A method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway.
swollen as from a fluid, bloated
Plasma Membrane
thin outer boundary of a cell that regulates the traffic of chemicals between the cell and its surroundings
Selective Permeability
feature of the plasma membrane that maintains homeostasis within a cell by allowing some molecules into the cell while keeping others out
(water channel proteins that facilitate the amount of diffusion)A transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane (osmosis).
Amphipathic Molecule
Example Phospholipid, , a molecule that has both a hydrophilic region and a hydrophobic region
Fluid Mosaic Model
The currently accepted model of cell membrane structure, which envisions the membrane as a mosaic of individually inserted protein molecules drifting laterally in a fluid bilayer of phospholipids.
A large amount of this in a phospholipid bilayer at High Temperatures reduces membrane fluidity, but at lower temperature prevents the membrane from solidifying.
Unsaturated lipids
What helps a membrane increase its overall fliudity by making more kinks avaliable to it at lower temperatures? Also explains why some plants have more of these in the autumn than the summer.
Integral Proteins
Typically transmembrane proteins with hydrophobic regions that completely span the hydrophobic Interior of the membrane.
Peripheral Proteins
Protein appendages loosely bound to the surface of the membrane and not embedded in the lipid bilayer.
a receptor protein built into the plasma membrane that interconnects the extracellular matrix and the cytoskeleton
function in support, adhesion, movement, and regulation (glycoproteins) collagen most abundant in animal cells
Membrane carbohydrates bound to lipids, take part in cell-cell recognition
a protein with one or more carbohydrates covalently attached to it.
Transport Proteins
proteins that span the plasma membrane creating a selectively permeable membrane that regulates which molecules enter and leave a cell
Channel Proteins
What kind of proteins open passageways through the membrane for certain hydrophilic substances such as polar and charged molecules? It is a type of transport protein.
Passive Transport
the movement of materials through a cell membrane without using energy or by diffusion (the concentration gradient itself acts as potential energy) .
Active Transport
energy-requiring process that moves material across a cell membrane against a concentration difference
Concentration Gradient
the path molecules travel when an imbalance between separated molecule concentrations exists
the process by which molecules move from an area of higher concentration to an area of lower concentration, because of thermal motion (heat)_
diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal
The ability of a solution surrounding a cell to cause that cell to gain or lose water. Must take both the concentration and the membrane.
describes a solution whose solute concentration is equal to the solute concentration inside a cell,NO NET movement
describes a solution whose solute concentration is lower than the solute concentration inside a cell, water will enter the cell which will eventually cause it to become more turgid and burst.
when comparing two solutions, the solution with the greater concentration of solutes, will lose water shrivel and then die. Can be accomplished by adding salt
The regulation of solute and water concentrations in body fluids by organisms living in hyperosmotic, hypoosmotic, and terrestrial environments.
Contractile Vacuole
Saclike organelles found in Paramesium that expand to collect excess water and contract to squeeze the water out of the cell when it is hyposmotic to the enviroment.
lacking firmness or stiffness, hypertonic (cell)
the contraction or shrinking of the cell membrane of a plant cell in a hypertonic solution in response to the loss of water by osmosis
Facilitated Diffusion
the transport of substances through a cell membrane along a concentration gradient with the aid of carrier proteins
Carrier Proteins
some transport proteins, called _____ ____, function by having a hydrophilic channel that certain molecules or atomic ions can use as a tunnel through the membrane
Ion Channels
a transmembrane protein channel that allows a specific ion to flow across the membrane down its concentration gradient
Gated Channels
closed most of the time sensitive to voltage, mechanical force, or ligand (molecule that binds to a receptor), open to both intra- and extracellular fluid, problems with channels can lead to disease ex. cystic fibrosis
Disease caused by a kidney transporter defect in a the kidney transporter involved in the reabsorption of some amino acids which leads to the excretion of cysteine, lysine, arginine, and ornithine. Cysteine (because it is the least soluable) forms calculi in kidney tubules.
Sodium Potassium Pump
A special transport protein in the plasma membrane of animal cells that transports sodium out of the cell and potassium into the cell against their concentration gradients.
Membrane Potential
The charge difference between a cell's cytoplasm and the extracellular fluid, due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances.
Electrochemical Gradient
The diffusion gradient of an ion, representing a type of potential energy that accounts for both the concentration difference of the ion across a membrane and its tendency to move relative to the membrane potential.
Electrogenic Pump
an ion transport protein that generates voltage across a membrane
Proton Pump
An active transport mechanism in cell membranes that uses ATP to force hydrogen ions out of a cell, generating a membrane potential in the process. Main type in plant, fungi and bacteria.
the coupling of the "downhill" diffusion of one substance to the "uphill" transport of another against its own concentration gradient
the process by which a substance is released from the cell through a vesicle that transports the substance to the cell surface and then fuses with the membrane to let the substance out
Bulk Transport
The process by which large particles and macromolecules are transported through plasma membranes. Inc. exocytosis and endocytosis. (Neurotransmitters)
The cellular uptake of macromolecules and particulate substances by localized regions of the plasma membrane that surround the substance and pinch off to form an intracellular vesicle. (Phagocytosis and Pinocytosis
A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes.
process in which extensions of cytoplasm surround and engulf large particles and take them into the cell
general term for any molecule that binds specifically to a receptor site of another molecule
Familial Hypercholesterolemia
A metabolic disorder that is caused by defective or absent receptors for LDLs on cell surfaces, that is marked by an increase in blood plasma LDLs and by an accumulation of LDLs in the body resulting in an increased risk of heart attack and coronary heart disease, and that is inherited as an autosomal dominant trait.
Receptor Mediated Endocytosis
The movement of specific molecules into a cell by the inward budding of membranous vesicles containing proteins with receptor sites specific to the molecules being taken in; enables a cell to acquire bulk quantities of specific substances.
four main classes of large biological molecules (carbohydrates, lipids, proteins, nucleic acids) Have a mass of over 100, 000 daltons.
Large compound formed from combinations of many monomers. 3/4 of macromolecules are this (Carbohydrates, Nucleic Acids, and Proteins) NOT Lipids.
Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen, non-polar.
A chemical process that lyses, or splits, molecules by the addition of water, functioning in disassembly of polymers to monomers. Opposite of a dehydration reaction.
the unit of measurement used to measure the mass of an atom and subatomic particles
One of the 4 main classes of biological molecules, ,contains carbon, hydrogen, oxygen, and nitrogen. source of energy. needed by tissue for repair and growth. made up of 20 amino acids.
One of the 4 main classes of biological molecules, Organic compounds made of carbon, hydrogen, and oxygen atoms usually in the proportion of 1:2:1.
Nucleic Acids
One of the 4 main classes of biological molecules are very long organic compounds made up of carbon, hydrogen, nitrogen, and phosphurous, contain instructions that cells need to carry out all the functions of life
a simple molecule that can combine with other like or unlike molecules in a dehydration reaction to make a polymer
The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, the molecular formulas of are generally some multiple of CH2O. Glucose, Sucrose, each molecule has a carbonyl group and multiple hydroxyl groups
Carbonyl group
C=O, an organic molecule, a functional group consisting of a carbon atom linked to a double bond to an oxygen atom, can either form an aldehyde or ketone depending on location.
Hydroxyl groups
A functional group consisting of a hydrogen atom joined to an oxygen atom by a polar covalent bond. Molecules possessing this group are soluble in water and are called alcohols.
Name of polysaccharide when carbonyl compound is at the end of a C-skeleton; glucose is an ex.
Name of polysaccharide when carbonyl compound is within the C-skeleton; fructose is an ex.
A double sugar, consisting of two monosaccharides joined by dehydration synthesis(also called a glycosidic linkage .
Glycosidic linkage
covalent bond formed between two monosaccharides by a dehydration reaction
a complex carbohydrate found chiefly in seeds, fruits, tubers, roots and stem pith of plants, notably in corn, potatoes, wheat, and rice which consists entirely of glucose monomers which are joined by 1-4 linkages, 2 main forms in plants (Amylose, amylopectin, stored within plastids
Linear (unbranched) polymer of D-glucose units.
This polysaccharide is one of the two components of starch, making up approximately 20-30% of the structure. The other component is amylopectin, which makes up 70-80% of the structure. Slower breakdown.
The second type of starch is_______________and is a branched polymer linked by 1(arrow)-4-alpha and 1 (arrow)-6-alpha-glycosidic linkages.70-80% of the structure, higher faster breakdown usually long term storage.
One of a family of closely related plant organelles, including chloroplasts, chromoplasts, and amyloplasts (leucoplasts).
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch. Most branched fastest possible breakdown time. Depleted every day if not replenished by food.
A structural polysaccharide of cell walls, consisting of glucose monomers joined by b-1, 4-glycosidic linkages. The MOST abundant organic compound on Earth. Arises from the beta ring structure for glucose, and gives it a never branched look which in plants is grouped into Microfibrils. When this compound is eaten by humans it cannot be broke down but instead abrades the digestive tract to produce mucus.
A threadlike component of the cell wall, composed of cellulose molecules
stomach chamber in cows and related animals in which newly swallowed plant food is stored and processed by bacteria.
A tough structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods.
lipid; made up of fatty acids and glycerol; protects body organs, insulates body, and stores energy in the body
Fatty acid
an organic acid that is contained in lipids, such as fats or oils, combines with gylserol to make fat.
Three-carbon compound with three hydroxyl groups; component of fats and oils. combines with fatty acids to make fat.
Ester Linkage
A condensation (water-releasing) reaction in which the carboxyl group of a fatty acid reacts with the hydroxyl group of an alcohol. Lipids are formed in this way.
a fat that consists of three fatty acids linked to one glycerol molecule; linkages that bond hydroxyl to carboxyl are called ester linkages
Saturated Fat
fat in which all three fatty acid chains contain the maximum possible number of hydrogen atoms, cannot by hydrogenated( Carbon single bonds)
Unsaturated Fat
A lipid made from fatty acids that have at least one cis double bond between carbon atoms which creates a kink in the struccture.
the most common form of CVD; a disease characterized by fatty plaques (atheromas) along the inner walls of the arteries.
adding hydrogen to unsaturated fatty acids, forcing the liquid to solidfy, creates trans fat(which are worse than saturated fats)
Adipose Cells
Cells that humans and other mammal stock their long-term food reserves (fats); also serve as cushioning and, when found in subcutaneous layer, as insulation
A lipid made of a phosphate group and two fatty acids; consists of a hydrophilic polar head and two non-polar hydrophobic tails; forms cellular membranes.
Phosphate Group
-OPO3^-2; organic phosphates; contributes neg charge to mc of which it is a part (like DNA); has potential to react with water releasing NRG
A type of lipid characterized by a carbon skeleton consisting of four rings with various functional groups attached.These all have the same ring pattern: three six-sided rings and one five-sided ring.
A steroid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids.
Molecules, usually proteins or nucleic acids, that act as catalysts in biochemical reactions.
chemical agents that selectively speed up chemical reactions without being consumed by the reaction and lower activation energy.
A polymer (chain) of many amino acids linked together by peptide bonds.
Amino acid
organic compounds containing an amino group and a carboxylic acid group. At the center is an asymmetric carbon called the alpha carbon. Also has a R group known as the side chain.
An amino acid; an important inhibitory neurotransmitter in the lower brain stem and spinal cord. Also the only one lacking an assymetric carbon.
Peptide Bond
covalent bond formed between amino acids
Frederick Sanger
English biochemist who determined the sequence of amino acids in insulin and who invented a technique to determine the genetic sequence of an organism (born in 1918)
Ribbon Model
Protein model showing how the single polypeptide chain folds and coils to form the functional protein
Space Filling Model
a molecular model in which atoms and their electron clouds are represented by spheres. The advantage is that it better represents the overlap of the electron clouds that occur in a molecule
Primary Structure
The first level of protein structure; the specific sequence of amino acids making up a polypeptide chain, whose order is determined by inherited genetic information.
Secondary Structure
The localized, repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bond formation between peptide linkages. The oxygen and nitrogen atoms are slighlty electronegative, so the weakly positive hydrogen bonds attatch to the nitrogen atom. Can be alpha helix or B- Pleated Sheet
Tertiary Structure
The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain. A hydrophobic interaction may contribute to the structure, van der Waal and disulfide bridges help hold and reinforce the conformationof the protein.
Quaternary Structure
The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits. Examples Collagens helical polypesptide chains and Hemoglobin2 4 poplypeptide subunits with a heme group
B-Pleated Sheet
One form of the secondary structure of proteins in which the polypeptide chain folds back and forth and the regions of the chain lie parallel to each other and are held together by hydrogen bonds.
a helix
A spiral shape constituting one form of the secondary structure of proteins, arising from a specific pattern of hydrogen bonding between very 4th amino acid.
Hydrophobic interaction
A type of weak chemical bond formed when molecules that do not mix with water coalesce to exclude the water usually found at the core of the protein, and van der Waals interactions hold them together .
Disulfide Bridges
Strong covalent bonds formed when the sulfur of one cysteine monomer bonds to the sulfur of another cysteine monomer which rivets parts of proteins together.
Heme Group
A group that is a large organic molecule with an iron atom at its center. It is made of heme, an oxygen transporter.
Sickle Cell Disease
The point mutation that results in the substitustion of valine for glutamic acid changes the primry structure which creates an exposed hydrophobic region which leads to a deformation (makes clumping more likely and diminished oxygen capacity in this disease.
For proteins, a process in which a protein unravels and loses its native conformation, thereby becoming biologically inactive. For DNA, the separation of the two strands of the double helix. Denaturation occurs under extreme conditions of pH, salt concentration, and temperature. Proteins can also become this if they are transfered from an aqueous environment to an organic solvent(because the hydrophobic parts would be switched to the outside).
A protein molecule that assists in the proper folding of other proteins. Work by keeping the polypeptide "separated from bad influences.
X- Ray Crystallography
A technique that depends on the diffraction of an X-ray beam by the individual atoms of a crystallized molecule to study the three-dimensional structure of the molecule.
way to study protein structure, gives spectra that shows atoms resonating at certain ranges, family of conformations
A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).
Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspring.
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
A type of RNA, synthesized from DNA, that attaches to ribosomes in the cytoplasm and specifies the primary structure of a protein; also called messenger RNA.
polymer consisting of many nucleotide monomers; serves as a blueprint for proteins and, through the actions of proteins, for all cellular activities
One of two families of nitrogenous bases found in nucleotides. Adenine (A) and guanine (G) are purines. Have a DOUBLE RING.
the family of smaller nitrogenous bases in which its members have 1 six-membered rings of carbon and nitrogen atoms; members include cytosine (C), thymine (T), and uracil (U)
A structure composed of a ribose molecule linked to one of the aromatic bases. In a deoxynucleoside, the ribose is replaced with deoxyribose. Does NOT contain the phosphate group.
Double Helix
The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape.
Phosphodiester linkage
covalent bonds that join adjacent nucleotides between the -OH group of the 3' carbon of one nucleotide and the phosphate on the 5' carbon of the next
the pattern that describes the formation of DNA; the two sugar-phosphate backbones run in opposite 5' >> 3' directions from each other, somewhat like a divided highway
The branch of biology concerned with the relations between organisms and their environment
nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate
the living organisms in an ecosystem
all the plant and animal life of a particular region
the number or amount of something., In Ecology questions relating to this are of prime importance
The arrangement of something across Earth's surface . In Ecology questions relating to this are of prime importance
the typical weather pattern in an area over a long period of time
Organismal Ecology
The branch of ecology concerned with the morphological, physiological, evolutionary, and behavioral ways in which individual organisms meet the challenges posed by their biotic and abiotic environments.
a group of organisms of the SAME species populating a given area
Population Ecology
The study of populations in relation to the environment, including environmental influences on population density and distribution, age structure, and variations in population size.
A group of interdependent organisms of all the species inhabiting the same region and interacting with each other
Community Ecology
focus on how interactions between species, such as predation, competition and symbiosis affect community structure and organization
Collection of all the organisms that live in a particular place, together with their nonliving environment.
Ecosystem ecology
The study of energy flow and the cycling of chemicals among the various biotic and abiotic components in an ecosystem
Landscape Ecology
the study of past, present, and future patterns of landscape use, as well as ecosystem management and the biodiversity of interacting ecosystems
localized variation in environmental conditions within an ecosystem, arranged spatially into a complex of discrete areas that may be characterized by distinctive groups of species or ecosystem processes
the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist
A social movement dedicated to protecting the earths life-support systems for us and all other forms of life, NOT to be confused with Ecology.
Precautionary Principle
A guiding principle in making decisions about the environment, cautioning to consider carefully the potential consequences of actions. An ounce of prevention is worth a pound of cure.
Aldo Leopold
(1888-1948) founder of the enviromental change, going green, turned chicken shed in shack for family to live in, wrote "Sand Country Almanac", caught own food, passion about nature.
The study of the past and present distribution of species in the context of evolutionary theory.
large supercontinent that existed 250 million years ago, the gradual breakdown of this lead to the biogeographic realms we now associate with.
the movement of individuals away from their area of origin or from centers of high population density
Potential Range
where a species could live if transplanted plus its actual living area.
Actual Range
For a transplant to be considered successful, soe of the organisms must not only survive in the new area but also reproduce there. If a transplant is successful then the potential range of the species is larger than its_________ . In other words, the species COULD live in certain areas where it currently does not.
To lay eggs
Anopheline Mosquitoes
The protist called plasmodium that causes malaria spends the first part of its life cycle in ________ and the second half of its life cycle inside of humans. Is usually associated with a specific type of habitat.
Spatial Heterogeneity
A concept parallel to ecosystem productivity, the species richness of animals is directly related to the species richness of plants in a certain habitat.
Temporal Heterogeneity
changes in competitive dominance over time because interactions are dynamic and environment fluctuates.
the degree of hotness or coldness of a body or environment (corresponding to its molecular activity)
the part of the earth's surface covered with water (such as a river or lake or ocean)
What is the main source of energy for life on Earth?
relative lengths of night and day, more reliable then temperature for cuing seasonal events such as flowering by plants or migration by animals.
What amplifies the effects of enviromental temperature by increasing heat loss due to evaporation and convection, also increases rate of evaporative cooling in animals.
the transfer of thermal energy by the circulation or movement of a liquid or gas
the process by which water changes from liquid form to an atmospheric gas
energy that is radiated or transmitted in the form of rays or waves or particles
The exudation of water droplets, caused by root pressure in certain plants.
climate patterns on the global, regional, and local level
climate within a small area that differs significantly from the climate of the surrounding area
Equatorial region between the Tropic of Cancer and the Tropic of Capricorn. It is characterized by generally warm or hot temperatures year-round, though much variation exists due to altitude and other factors.
Mediterranean Climate
the mixing of waters as a result of changing water-temperature profiles in a lake, helps brig nutrient rich water through Spring and August
a broad, regional type of ecosystem characterized by distinctive climate and soil conditions and a distinctive kind of biological community adapted to those conditions.
Photic Zone
Portion of the marine biome that is shallow enough for sunlight to penetrate and where the majority of photosynthesis occurs .
Pelagic Zone
The area of the ocean past the continental shelf, with areas of open water often reaching to very great depths.
Benthic Zone
bottom of an aquatic ecosystem; consists of sand and sediment and supports its own community of organisms
Aphotic Zone
the part of the ocean beneath the photic zone, where light does not penetrate sufficiently for photosynthesis to occur.
..., organisms (plants and animals) that live at or near the bottom of a sea
Littoral Zone
..., a shallow zone in a freshwater habitat where light reaches the bottom and nurtures plants
Limnetic Zone
Area in a freshwater habitat away from the shore but still close to the surface
Neritic Zone
The region of shallow ocean water over the continental shelf.
Abyssal Zone
the deep sea (2000 meters or more) where there is no light
Continental Shelf
a gently sloping, shallow area of the ocean floor that extends outward from the edge of a continent
Oceanic Zone
vast open ocean from the edge of the continental shelf outward
In water, a distinctive temperature transition zone that separates an upper layer that is mixed by wind (the epilimnion) and a colder, deep layer that is not mixed (the hypolimnion)
large natural bodies of standing freshwater formed when precipitation, runoff, or groundwater seepage fills depressions in the earth's surface.
Ecosystems of several types in which vegetation is surrounded by standing water during part or most of the year, home to a diverse array of species, may be of three types (Basin, Riverine, and Fringe)
a large stream of water of natural origin which drains an area of land and flows into another river or body of water, are distinguished by their fast flowing current. Salt and nutrient content typically increases as they get to the mouth.
Transition area where fresh water from streams and rivers spill into the ocean, during rising tide seawater will flow up it, and flow out of it during falling tide. The denser seawater is usually found near the bottom. Are used as feeding grounds and are crucial feeding grounds for semi-aquatic vertebrates.
Fringe Wetland
A wetland occurring along the coasts of large lakes and seas, where water flows back and forth because of rising lake levels or tidal action (thus it includes both freshwater AND marine biomes).
Basin Wetland
A wetland that develops in a shallow basin, ranging from upland depressions to filled in lakes and ponds.
Riverine Wetland
A wetland that develops along shallow and periodically flooded rivers and streams.
Oligotrophic Lakes
Lakes that have a small supply of plant nutrients are called oligotrophic (poorly nourished) lakes but are generally oxygen rich. Often, this type of lake is deep and has steep banks. (Not Productive)
Eutrophic Lakes
Lakes that are nutrient rich and often depleted of oxygen in the deepest zone in summer and if ice covered in winter
Temperate Lakes
Are lakes that have a seasonal thermocline.
Tropical Lowland Lakes
Are lakes that have a thermocline all year round.
Intertidal Zone
an area along ocean shorelines that is repeatedly covered and uncovered by ocean tides, because it experiences longer exposure to air it has greater variation, the stresses(salinity, temperature, wave action) act to limit the distribution of animals in this biome. Most animals have some adaptation that allows them to attach to a substrate. Oil pollution has caused a severe decline in beach nesting birds and sea turtles.
Marine Benthic Zone
Consists of the seafloor below the surface waters of the coastal zone or neritic zone and the offshore pelagic zone zone. Except for shallow, near-coastal areas, this aquatic biome receives no sunlight. Organisms in the very deep benthic zone receive no sunlight and are adapted to continuous cold and extremely high pressure. Oxygen is usually available are associated deep sea hydrothermal vents. obtain enrgy by oxidizing H2S by a reaction of hot water with Sulfate.
Coral Reefs
Prominent oceanic features composed of hard, limy skeletons (CaCO3) produced by coral animals; usually formed along edges of shallow, submerged ocean banks or along shelves in warm, shallow, tropical seas. Limited to the Photic Zone, and are sensitive to temperaturea below 18degrees celsius and above 30. Dionaflagette algae,cnidarians are the predominant species, Global Warming and pollution may be leading to the large scale destruction.
Oceanic Pelagic Biome
Most of the ocean's waters far from shore, is mixed by ocean currents. This biome covers approximately 70% of the Earth Surface. Most common organisms are phytoplankton., jellies, worms krills, squids fishes and marine animals. Overfishing is a deep concern in this region
shows profiles of precipitation and temperature for various biomes to show the impact of climate on the distribution of organism. Remember it is based on the AVERAGE and the pattern of climatic variation.
a statistical relation between two or more variables such that systematic changes in the value of one variable are accompanied by systematic changes in the other
A cause and effect relationship in which one variable controls the changes in another variable.
The uppermost layer of vegetation in a terrestrial biome
Low Tree Stratum
layer of trees directly under the canopy
Ground Layer
Layer of the rainforest with very limited diversity
A non-woody, non-grass species of plant feound in broadleaf forests.
The transition from one type of habitat or ecosystem to another, such as the transition from a forest to a grassland.
Tropical Forest
A terrestrial biome characterized by high levels of precipitation(seasonal) 200-400 cm and high temperatures year-round. Stratified and competition for light is very intense. Large amount of epiphytes cover the trees, but are less abundant in the dry versions of these, Exhibits the highest animal diversity of any terrestrial biome, rapid population growth and human expansion are now destroying this biome.
Biome in which evaporation exceeds precipitation and the average amount of precipitation is less than 25 centimeters (10 inches) a year. Such areas have little vegetation or have widely spaced, mostly low vegetation, large amount of succulent plants (like cacti), reduced ;leaf surface area, C4 or CAM photosynthesis. Animals include scorpions, ants bettles lizards, seed eating rodents. Conversion to irrigated agriculture and increased urbanization have reduced the natural biodiversity of this biome.
A tropical grassland biome with scattered individual trees, large herbivores, and three distinct seasons based primarily on rainfall, maintained by occasional fires and drought. Plants are usually thorny with reduced leaf surface area. Warm all year round. Large Mammals like wildebeests and Zebras, Lions and Hyenes are common inhabitants, There is also evidence that the earliest humans lived in this biome, fires help mantain this biome while farming and overhunting is leading to a decline in large mammal population.
The matorral, maquis, garigue and Fynbos are all examples of this biomes, Usually occurs in mid altitude coastal areas but is very far flung, Precip. is highly seasonal(30-50) with rainy winters and long, dry summers. Dominated by shrubs and small trees, along with a high diversity of grasses and herbs. Temp. in Summer can reach 40 degrees Celsius. Plants have adapted by having tough evergren leaves of woody plants that reduce water loss.
Temperate Grassland
Pampas, Steppes, Veldts, Puszta are all examples of this. , a biome similar to savanna; characterized by low precipitation and lack of trees, except along stream courses, such as the prairies of North America, highly seasonal precipitation, Winters are cold, Summers are hot, common plants are grasses and forbs., plants are adapted to periodic droughts and to fire. Grazing of animals helps prevent woody shrubs and trees. Fertile soils make it an ideal place for agriculture.
Coniferous Forest
Also known as Taiga(the largest terrestrial biome on Earth), precipitation goes from 30 to 70 cm( Although coastal coniferous forest gets up to 300 cm of annual precipitation. Winters are usually cold and long summers may be hot. Moose, Brown Birds, Tigers and insects (which occasionally outbreak and kill vast amount of trees), Old growth may start to disappear.
Treeless arctic or alpine biome characterized by cold, harsh long winters, a short growing season, and potential for frost any month of the year (permafrost) ;mostly herbaceous vegetation includes low-growing perennial plants, mosses and lichens. Large Grazing musk Ox are residents, while caribou and reindeer, and birds are migratory.
Temperate Broadleaf Forest
A biome located throughout midlatitude regions( and also in small places in Australia) where there is sufficient moisture to support the growth of large, broadleaf deciduous trees. Precipitation is 70-120 cm( equally throughout all seasons). Few Epiphytes, most common in NA is decidous while in Aussie it is Eucalyptus. Most of the original types of these biomes have been destroyed by over logging.
Perennially frozen layer of the soil that forms when the water there freezes. It is found in arctic tundra.
Alpine Tundra
type of tundra that that occurs above the limit of tree growth but below the permanent snow line on high mountains; vegetation is similar to the arctic tundra but receives more sunlight and has no permafrost layer
plants such as mosses, lichens, and orchids, that grow on other plants but do not take nutrients from them
Population Ecology
The study of populations in relation to the environment, including environmental influences on population density and distribution, age structure, and variations in population size.
a group of organisms of the same species populating a given area, can be described in terms of density and dispersion
The number of individuals per unit area(volume)
The pattern of distribution of organisms in a population
Mark-Recapture Method
A sampling technique used to estimate the size of animal populations., Capture a few organisms, tag them, put the back into the environment, and then recapture and the # of tagged organisms caught helps tell total population, assumes that chances of being recaught are the same for every animal.
migration into a place (especially migration to a country of which you are not a native in order to settle there)
migration from a place (especially migration from your native country in order to settle in another)
Describing a dispersion pattern in which individuals are aggregated in patches. Is the MOST common types of dispersion (think Wolf's, Mayflies)
Describing a dispersion pattern in which individuals are evenly space, this may result from direct interaction(such as secretion of chemicals that inhibit competition, usually anagonistic and might extend to territoriality
the defense of a bounded physical space against encroachment by other individuals
Describing a dispersion pattern in which individuals are spaced in a patternless, unpredictable way, only occurs in the absence of strong attractions or repulsions among individuals, where key resurources and chemical factors are spread homogeneously.
the study of the vital statistics of populations and how they change over time, especially death/ birth rates, dispersion, and density. Can usually be sumarized with a Life Table
Life Table
A summary of how survival and reproductive rates in a population vary with the age of individuals; in species for which age is not informative or is difficult to measure, are often based on the size or life history stage of individuals. Best way to consturct one is by following a cohort
A population group unified by a specific common characteristic, such as age, and subsequently treated as a statistical unit.
Tioga Pass Belding's Ground Squirrel
Study by Sherman and Morton conducted a study of this animal (Spermophilus belding), figured out that males hae higher death rates than females in the population, and involved a cohort. (Type 2 Curve)-constant
Survivorship Curve
A plot of the number of members of a cohort that are still alive at each age; one way to represent age-specific mortality obtained by constructing a Life Table.
Type 1 Curve
Exhibeted by animals that produce few offspring, but good care increases their survival rate to maturity, so the curve is relatively flat at the begining then starts to curve downwards after middle age. (Humans, large mammals)
Type 2 Curve
Indicates that death rates do not vary much with age ; lizards, small mammals, big birds, old individuals are as likely to die as young ones
Type 3 Curve
Indicates that death rates for a population peaks early in life ; species that produce many small offspring and provide little or no parental care ( clams)
Reproductive Table
fertility schedule- age specific summary of reproduction rate in a population
Life History
The traits that affect an organism's schedule of reproduction and survival. Involves 3 basic variables (WHEN reproduction begins, How often an animal reproduces, and HOW many offspring are produced per reproductive cycle.
A life history in which adults have but a single reproductive opportunity to produce large numbers of offspring, such as the life history of the Pacific salmon, Agaves ; also known as big-bang reproduction. Also called BIG BANG REPRODUCTION or one shot, is favored in environments that are unpredictable because it increases the chances that some will survive.
latin; means :a single time
latin for beget
Also called century plants, are plant that grow in a semiarid environment, they grow for several years and then send up o huge flowering stalk, produce seeds and then die, the irregular water production may prevent seed production or seeding establishment for some time.
A life history in which adults produce large numbers of offspring over many years; also known as repeated reproduction. (Lizards) Favored in more dependent environments.
latin: to repeat
Per Capita Birth Rate
The expected number of offspring produced per unit time in a population of any size. (The average number of births per individual during the specified time interval). If individuals cannot obtain sufficient resources to reproduce, the per capita birth rate will decline.
Per Capita Death Rate
The expected number of deaths per unit time in a population of any size. (The average number of deaths per individual during the specified time interval). If individuals cannot consume enough energy, the per capita death rate will increase.
Per Capita Rate of Increase
the average contribution of each individual to population on growth. "per person"
( r )
to calculate: 100 individuals, 50 births, 20 deaths
50-20=30: net increase
Zero Population Growth
when a population is stable, neither growing nor decreasing. globally, this would occur when the birth rate and the death rate are the same (ZPG)
Exponential Population Growth
The geometric increase of a population as it grows in an ideal, unlimited environment. Under the condition of abundant food and resources( plus freedom to reproduce to capacity) we may assume the intrinsic rate of increase (J shaped Curve
Intrinsic rate of increase
the difference between the number of biths and the number of deaths, symbolized as r-max; the maximum population growth rate
Carrying Capacity
largest number of individuals of a population that a environment can support (symbolized by K)
Logistic Growth Model
a description of idealized population growth that is slowed by limiting factors as the population size increases nad carrying capacity. (S shaped Curve)
Allee Effect
For smaller populations, the reproduction and survival of individuals decrease; arising from behavioral or ecological factors, such as difficulties in finding mates in animals.
The concept that in certain populations, life history is centered around producing relatively few offspring that have a good chance of survival (iteroparous), density dependent selection. tENDS TO MAXIMIZE POPULATION LIMIT.
The concept that in certain populations, a high reproductive rate is the chief determinant of life history(semalparous), also called density independent selection. Tends to maximize rate of increase
Surrounding the topic of _____________ of population growth, THERE ARE 2 FACTORS (What stops an animal population from growing) ,and why do some populations show large fluctuateions while others remaine stable.
Density Dependent
Referring to any characteristic that varies according to an increase in population density. (Negative Feedback Loop)
Density Independent
referring to any characteristic that is not affected by population density
Population Dynamics
The study of how complex interactions between biotic and abiotic factors influence variations in population size.
the practice of eating the flesh of your own kind, helps limit the Dungeness Crab
Dungeness Crab
small edible crab of Pacific coast of North America, that practices cannibalism and whose population fluctuates from a couple thousand to hundreds of thousands many times ever 10 years.
A collection of populations that have regular or intermittent gene flow between geographically separate units
Age Structure
the relative number of individuals of each age in a population (commonly represented in Pyramids)
Infant Mortality
The number of infant deaths per 1,000 live births
Demographic Transition
change in a population from high birth and death rates to low birth and death rates ( is associated with a n increae in basic health care , are the most dramatic in China)
Life Expectancy at Birth
The predicted average length of life at birth.
Anton Von Leeuwenhoek
1st scientist to observe cells using a simple microscope, also in 1679 he provided the first estimate of the Global Carrying Capicity of the human population at 13.4 billion.
Ecological Footprint
A calculation that shows the productive area of Earth needed to support one person in a particular country (uses arable land, pasture, oceans, built up land ,and fossil energy)
Ecological Capacity
the actual resource base of each country
What keeps on increasing humans carrying capacity, however all populations must stop growing sooner or later.
A group of interdependent organisms inhabiting the same region and interacting with each other
Interspecific Interactions
interactions between 2 or more different types of species (includes competition, predation, herbivory, and symbiosis
the relation between two different species of organisms that are interdependent
the struggle between organisms to survive in a habitat with limited resources
symbiotic relationship in which both species benefit from the relationship. +/+
the relation between two different kinds of organisms when one receives benefits from the other without damaging it. +/0
a relationship between two species in which one species benefits and from the other species, which is harmed, involves a host
any change, other than an injury, that disrupts the normal functions of the body, +/-
an animal or plant that nourishes and supports a parasite
an organism that lives in or on another organism; one who lives off another person
an interaction in which one organism captures and feeds on another organism. +/-
Interspecific Competition
in a community competition for limited resources between members of different species
Competitive Exclusion
The concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population, This principle can be used to predict fundamental ecological niches
Carrying Capacity
largest number of individuals of a population that a given environment can support
Ecological Niche
the sum of a species' use of the biotic and abiotic resources in its environment. Like a "profession".
Fundamental Niche
The full potential range of the physical, chemical, and biological factors a species can use if there is no competition from other species.
Realized Niche
the range of resources and conditions a species actually uses or can tolerate at optimal efficiency; smaller than fundamental niche
Resource Partitioning
The division of environmental resources by coexisting species such that the niche of each species differs by one or more significant factors from the niches of all coexisting species
Allopatric Speciation
The formation of a new species as a result of an ancestral population's becoming isolated by a geographic barrier resulting in distrupted gene flow.
Sympatric Speciation
The formation of a new species as a result of a genetic change that produces a reproductive barrier between the changed population (mutants) and the parent population. No geographic barrier is present.
Character Displacement
the tendency for characteristics to be more divergent in sympatric populations of two species than in allopatric populations of the same two species. An example is Darwin's Finches
Seed Predators
Animals that chew up or digest plant seeds
Cryptic Coloration
camouflage, , , makes potential prey difficult to spot against its background is a defensive mechanism.
Aposematic Coloration
The bright coloration of animals with effective physical or chemical defenses that acts as a warning to predators (Posion Frogs)
Batesian Mimicry
A type of mimicry in which a harmless species looks like a species that is poisonous or otherwise harmful to predators
Mullerian Mimicry
evolution of two species both of which are unpalatable and have poisonous stingers or some other defense mechanism to resemble each other, leads into the gain of successive advantage .
not pleasant or acceptable to the taste or mind
An interaction in which an herbivore eats parts of a plant or alga. +/- interaction
Wide variety of chemical compounds. May interfere with DI tracts of insect herbivores and inhibit microbial growth.
parasites that live within the body of their host like roundworms
Organisms, such as fleas, that live in the exterior of another organism (the host) and obtain food from it.
A type of parasitism in which an insect lays eggs on or in a living host; the larvae then feed on the body of the host, eventually killing it
A phylum of nonsegmented intestinal helminths characterized by having an anterior attachment organ (proboscis) covered with spines; also called spiny-headed worms. Alter behavior in crustaceans in a way that maximizes the probability of transmittance.
an organism that produces disease in a host organism disease being alteration of one or more metabolic functions in response to the presence of the organism
Sudden Oak Death
caused by Phytophthora ramorum
West Nile Virus
A flavivirus infection is transmitted by mosquitoes and is relatively new to the United States and can cause flu-like symptoms that can result in encephalitis
the process in which species exert selective pressure on each other and gradually evolve new features or behaviors as a result of those pressures
Species Diversity
the number and relative abundance of species in a biological community
Species Richness
the number of different species in a community
Relative Abundance
Proportional representation of a species in a community or sample of a community
Trophic Structure
The different feeding relationships in an ecosystem, which determine the route of energy flow and the pattern of chemical cycling
Food Chain
series of steps in an ecosystem in which organisms transfer energy by eating and being eaten
Food Webs
A complex diagram representing the many energy pathways in an ecosystem
Energetic Hypothesis
The concept that the length of a food chain is limited by the inefficiency of energy transfer along the chain. One of two along with the Dynamic stability Hypothesis
Dynamic Stability Hypothesis
A theory suggesting that food chain length is limited because longer food chains are less stable and higher level consumers would be at a higher risk of extinction( because predators would be slower to rebound after an ecological change.
Dominant Species
Those species in a community that have the highest abundance or highest biomass. These species exert a powerful control over the occurrence and distribution of other species.
Keystone Species
a species that is critical to the functioning of the ecosystem in which it lives because it affects the survival and abundance of many other species in its community
Invasive Species
plants and animals that have migrated to areas where they did not originate; often displace native species by outcompeting them for resources(exotic species)
Foundation Species
Species that plays a major role in shaping communities by creating and enhancing a habitat that benefits other species.
A species that has a positive effect of the survival and reproduction of other species in a community and that contributes to community structure.
Bottom- up Model
A model of community organization in which mineral nutrients control community organization because nutrients control plant numbers, which in turn control herbivore numbers, which in turn control predator numbers N +o V +o H, +o P
Top Down Model
A model of community organization in which predation controls community organization because predators control herbivores, which in turn control plants, which in turn control nutrient levels; also called the trophic cascade model.
Nonequilibrium Model
The model of communities that emphasizes that they are not stable in time but constantly changing after being buffeted by disturbances.
A discrete event that disrupts an ecosystem or community. Examples are fires, hurricanes, tornadoes, droughts, and floods. Examples of human-caused disturbances include deforestation, overgrazing, and plowing.
Intermediate disturbance hypothesis
The concept that moderate levels of disturbance can foster greater species diversity than low or high levels of disturbance.
Ecological Succession
series of changes in the species in a community, often following a disturbance
Primary Succession
an ecological succession that begins in a an area where no biotic community previously existed
Secondary Succession
succession following a disturbance that destroys a community without destroying the soil. Yellowstone Fire in 1988 for example.
unsorted sediments deposited directly from glacial ice at the end or side of the glacier
any of various pale or ashy mosses of the genus Sphagnum whose decomposed remains form peat
The loss water from the soil through both evaporation and transpiration from plants.
Actual Evapotranspiration
the amount of water annually transpired by plants and evaporated from a landscape, usually measured in millimeters.
Potential Evapotranspiration
a measure of energy availability but not water availability is determined by the amount of solar radiation and temperature is highest in regions of high solar radiation and temperature
German naturalist who explored Central and South America and provided a comprehensive description of the physical universe (1769-1859)
Species Area Curve
the biodiversity pattern, first noted by Alexander von Humboldt, that illustrates that the larger the geographic area of a community, the greater the number of species (ceteris paribus).
Island Equilibrium Model
model of speciation where the equilibrium number of species will be at where the immigration rate meets the extinction rate
Integrated Hypothesis
The concept, put forth by F. E. Clements, that a community is an assemblage of closely linked species, locked into association by mandatory biotic interactions that cause the community to function as an integrated unit, a sort of superorganism. Emphasizes study groups of species.
Individualistic Hypothesis
The concept, put forth by H. A. Gleason, that a plant community is a chance assemblage of species found in the same area simply because they happen to have similar biotic requirements. Emphasizes studying individual species. Generally accepted today,
Rivet Model
the concept, put forth by Paul and Anne Ehrlich, that many or most of the species in a community are associated tightly with other species in a web of life. according to this model, an increase or decrease in one species in a community affects many other species.
Redundancy Model
The concept, put forth by Henry Gleason and Brian Walker, that most of the species in a community are not tightly coupled with one another (that is, the web of life is very loose). According to this model, an increase or decrease in one species in a community has little effect on other species, which operate independently.
Consists of all the organisms living in the community as well as all the abiotic factors with which they interact. Boundaries of this are not discernable. Involves two processes, energy flow and chemical cycling.
What all energy in an ecosystem enters as before being converted by autotrophs into chemical energy which is used by heterotrophs in the organic compounds of food, and then dissapated of heat.
loose bits and pieces of material resulting from disintegration or wearing away; fragments that result from any destruction
Law of conservation of energy
the law that states that energy cannot be created or destroyed but can be changed from one form to another
Primary Producers
An autotroph, usually a photosynthetic organism. Collectively, autotrophs make up the trophic level of an ecosystem that ultimately supports all other levels.
Primary Consumers
this category includes organisms that consume producers (plants and algae) and have to be herbivores.
organisms that mainly prey upon animals.
organisms that eat only plants
Secondary Consumers
The carnivores in an ecosystem; organisms that feed on primary consumers(herbivores)
Tertiary Consumers
Animals that feed on animal-eating animals. They feed at high trophic levels in food chains and webs. Examples are hawks, lions, bass, and sharks.
organism that obtains energy from the foods it consumes; also called a consumer
organisms that eat both plants and animals
organisms that feed on the detritus and decomposing organic material of living organisms, are the major link between primary producers and consumers in an ecosystem. Mainly prokaryotes ( bacteria/ archea) and fungi. They also account for most of the conversion of organic materials from all trophic levels to inorganic compounfs usuable by primary consumers.
Primary Production
the amount of LIGHT energy converted to chemical energy (organic compounds) by autotrophs in an ecosystem during a given time period, sets the limit for the budget of the entire ecosystem.
Gross primary production
the amount of light energy that is converted to chemical energy by photosynthesis per unit time, more than net primary production because of inefficency. (GPP) Equation is NPP + R = GPP
Net Primary Production
The gross primary production of an ecosystem minus the energy used by the producers for respiration. (NPP). Equation is GPP - R = NPP, is the key measurment because it represents the true storage of chemical energy in an ecosystem. New
Standing Crop
the total biomass of photosynthetic autotrophs present at a given time, not to be confused with NPP
Rain Forest
a forest region located in the Tropical Zone with a heavy concentration of different species of broadleaf trees. Has the highest average NPP value.
Photic Zone
Regions of a body of water where light penetrates, enabling photosynthesis, the depth of this is an important factor in a regions primary production, along with limiting nutrients.
Limiting Nutrients
The most important factor that limits primary production, is the element that must be added in order for production to increase in a particular area. Is usually nitrogen or phosphorous( and are usually very low in the photic zone)
Southern Ocean
This ocean, often not labled on maps, surrounds Antarctica and extends northward toward Australia, has the largest area of upwelling (nutrient rich waters circulating to the open surface), which stimulates growth of phytoplankton populations and increase primary production.
The buildup over time of nutrients in freshwater lakes and ponds that leads to an increase in the growth of algae, usually lead to the loss of all but the most tolerant species, which would reduce biodiversity.
Actual Evapotranspiration
The amount of water transpired by plants and evaporated from a landscape over a given period of time, usually measured in millimeters and estimated for a year. Related to the fact that temperature and moisture are the key factors that control primary production in terrestrial ecosystems. It INCREASES with the amount of precipitation in a region and the amount of solar energy available.
the average kinetic energy of the individual particles, in a terrestrial environment it along with moisture are the main factors affecting primary production.
Secondary Production
The amount of chemical energy in consumers' food that is converted to their own new biomass during a given time period
20 %
Energy transfer between trophic levels is usually less than _____
Net Secondary Production
The energy stored in biomass represented by growth and reproduction.
Production Efficiency
The percentage of energy stored in food that is not used for respiration or eliminated as waste.
____________ usually have higher production efficencies then endotherms.
Trophic Efficiency
The ratio of the biological production of one trophic level to the biological production of the next lower trophic level, are always less than production effeciences because they take into account energy lost through respiration and contained in feces.
Pyramid of Net Production
the representation of the loss of energy with each transfer in a food chain in which trophic levels are stacked in blocks, with primary producers forming the foundation of the pyramid
Biomass Pyramid
diagram representing the biomass in each trophic level of an ecosystem, most sharply decrease while some aquatic ecosystems have inverted biomass biomass resulting from phytoplankton having such a short turnover time., howver the pyramid of production is still the same.
Turnover time
The time required to replace the standing crop of a population or group of populations (for example, of phytoplankton), calculated as the ratio of standing crop biomass to production
The relative ______ of the food chain limits the overall biomass of top level carnivrores and the number of trophic levels to about 4 or 5.
Pyramid of Numbers
A diagrammatic representation of the number of individual organisms present at each trophic level in an ecosystem
Green World Hypothesis
Explains why most terrestrial ecosystems are green., The conjecture that terrestrial herbivores consume relatively little plant biomass because they are held in check by a variety of factors, including predators, parasites, and disease
Gypsy Moth
brought to US from Eurasia to breed hardier silk worm; $500 mil spent on control; lack of natural predators in US, an exotic species( One of the 4 main factors reducing biodiversity).
Biogeochemical cycles
process in which elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another
when meteoroids enter Earth's atmosphere, are the only exterrestrial source of new matter.
Water Cycle
The continuous movement of water from the ocean to the atmosphere to the land and back to the ocean, main processes that drive it are the evaporation of liquid water, condensation of water vapors into clouds, and precipitation
The Carbon Cycle
The cycle that describes:carbon in CO2 is incorporated into plants by photosynthesis, then into animals by consuming organisms, and returned to the air as CO2 from respiration. Cellular carbon is returned to the soil through waste and dead organism decay.
The Nitrogen Cycle
Nitrogen-fixing bacteria live in the roots of legumes and convert free nitrogen (N2) into the ammonium ion (NH4+). Nitrifying bacteria convert the ammonium ion into nitrites (NO2-) and then into nitrates (NO3-). Dentrifying bacteria convert nitrates into free atmospheric nitrogen (N2).
Nitrogen Fixation
the assimilation of atmospheric nitrogen by soil bacteria and its release for plant use on the death of the bacteria, some is also fixed by lightning
A process in the nitrogen cycle where soil bacteria convert organic nitrogen to ammonia
the oxidation of ammonium compounds in dead organic material into nitrates and nitrites by soil bacteria (making nitrogen available to plants)
Anaerobic process in which fixed nitrogen compounds are converted back into nitrogen gas and returned to the atmosphere
The Phosphorous Cycle
a sedimentary cycle in which only a small amount is available to plants by the weathering of the rocks; the biotic community recycles phosphorus back to the producers, temporarily incorporating it into ATP, nucleotides, teeth, bone and shells, and then returning it to the ecosystem via decomposition
Abbreviation of a long term ecological research that is taking place in forest ecosystems since 1963 in the Whit Mountains of New Hampshire.
Critical Load
the amount of added nutrient, usually nitrogen or phosphorus, that can be absorbed by plants without damaging ecosystem integrity. Anything that is over this runs into other ecosystems choking waterways and killing fish
a condition of a lake or other body of water characterized by low nutrients, low productivity, and HIGH oxygen levels in the water column.
Cultural Eutrophication
Overnourishment of aquatic ecosystems with plant nutrients (mostly nitrates and phosphates) because of human activities such as agriculture, urbanization, and discharges from industrial plants and sewage treatment plants.
a condition in a lake or other body of water that is characterized by lush phytoplanktonic growth followed by high amounts of decay in the bottom resulting in depletion of oxygen in the water column. May be supersaturated with the oxygen produced in the day but anoxic(oxygen- poor) at night when respiration occurs.
Acid Precipitation
rain containing acids that form in the atmosphere when industrial gas emissions (especially sulfur dioxide and nitrogen oxides) combine with water , leads to calcium and other ions or granite(which is affected the most) because of the low amount of bicarbonate. to leach from the soil which creates nutrient deficiencies.
Biological Magnification
Increasing concentration of a harmful substance in organisms at higher trophic levels in a food chain or food web. Example DDT, and PCB's (polychlorinated biphenyls)
The 1976 Toxic Substance Control Act specifically banned the production and use of what substance? Also known as polychlorinated biphenyls, itsuppress the immune system, cause cancer in humans, aquatic ecosystems (bad for reproduction since the babies retain high levels of PCB ,and was put into transmitters.)
Dichlorodiphenyltrichloroethane, a chlorinated hydrocarbon that has been widely used as a pesticide but is now banned in some countries.
1976 Toxic Substance Control Act
Allows for control and testing of chemicals that have potential negative impact to human life or the environment. Banned DDT and PCB's
Silent Spring
A book written to voice the concerns of environmentalists. Launched the environmentalist movement by pointing out the effects of civilization development. By Rachel Carson.
C3 Plants
More then 95 % of plants on the earth are this. A plant that changes C02 into a three carbon compound before entering the Calvin cycle for photosynthesis.
C4 Plants
A plant that prefaces the Calvin cycle with reactions that incorporate CO2 into four-carbon compounds, the end product of which supplies CO2 for the Calvin cycle. Are outproduced by C3 plants in a very high oxygen environment.
Stands for the Forest- Atmosphere Carbon Transfer and Storage Emperiment. Manipulated the concentration of CO2
Greenhouse Affect
The balance of the amount of heat being reflected back to earth by the atmosphere controled by the amount of greenhouse gases in the atmosphere, normally elavates the temperature from about - 18 degrees celsuis, making living life possible.
Kyoto Protocol
establishes legally binding commitments for the reduction of four greenhouse gases (carbon dioxide, methane, nitrous oxide, sulfur hexafluoride), and two groups of gases (hydrofluorocarbons and perfluorocarbons) Took place in Rio De Janeiro in 1992, U.S. withdrew in 1997.
O3, a form of oxygen that has three oxygen atoms in each molecule instead of two. protects us from dangerous ultraviolet radiation from the sun
chloroflourocarbons human made organic compounds containing Cl and Flourine several industrial and commercial applications but are now banned (1978) because they attack ozone layer which protects us from ultraviolet radiation, most apparent over antartica.
Montreal Protocol
meeting in 1987 where a group of nations met in Canada and agreed to take steps to fight against Ozone Depletion-CFC's banned
Rosy Periwinkle
Catharanthus roseus, , native to madagascar. source of 2 natural alkaloids agents that are highly successful in treating childhood leukemia and Hodgkin's disease.
Conservation biology
Multidisciplinary science created to deal with the crisis of maintaining the genes, species, communities, and ecosystems that make up earth's biological diversity. Its goals are to investigate human impacts on biodiversity and to develop practical approaches to preserving biodiversity.
Restoration Ecology
A goal-directed science that applies ecological principles in an effort to return degraded ecosystems to conditions as similar as possible other natural, predegraded state.
Equatorial region between the Tropic of Cancer and the Tropic of Capricorn. It is characterized by generally warm or hot temperatures year-round, though much variation exists due to altitude and other factors. MOST species live in these areas.
Cretaceous Period
By some estimates we are currently in the process of pushing more species towards extinction than in the ____________________ 65 million years ago.
disappearance of a species from all parts of its geographical range, occurs naturally, so in itself it is not the problem, the rate of it is.
Ecosystem Engineer
A dominant species that influences its community by creating, modifying, or maintaining physical habitat for itself and other species.
Refers to the biological diversity, and has 3 main components, Genetic diversity, species diversity, and ecosystem diversity
Genetic diversity
The individual genetic variation within a population, and between populations that is associated with adaptations to local conditions , loss of some genetic diversity might make microevolution impossible, which could lead to loss of genetic resources that could improve disease resistance in crops through plant breeding.
Species diversity
refers to the number of different species an ecosystem or within the biosphere
Ecosystem diversity
variety of habitats, living communites, and ecological processes in the living world
The process whereby a specific segment of DNA is copied or cloned many times (amplification) using DNA polymerase, The base pair sequence of each end of the target must be known
Endangered Species
a species that is in danger of extinction throughout all or a significant portion of its range
Threatened Species
a species that could become endangered in the near future
mandates that listed animals be protected
the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist
various tropical and subtropical freshwater fish - many are popular as aquarium fish, loss of a about 200 of these species in Lake Victoria is a major concern.
Keystone Predator
a predator species that reduces the density of the strongest competitors in a community, thereby helping maintain species diversity
having to do with the banks of a body of water
the connections that human beings subconsciously seek with the rest of life
Hodgkin's disease
painless progressive enlargement of lymph nodes, spleen, and lymphoid tissue; symptoms include anorexia, lassitude, weight loss, fever, itching, night sweats, and anemia
Ecosystem Services
Important environmental benefits, such as clean air to breathe, clean water to drink, and fertile soil in which to grow crops, that ecosystems provide
Introduced Species
0ne of the 4 major major threats to biodiversity,a species moved by humans, either intentionally or accidentally, from its native location to a new geographic region; also called an exotic, invasive, or nonnative species.
A hardy vine that has compound leaves and purplish flowers and roots that contain a nourishing starch used medicinally. It is an invasive weed in the southeastern United States but is native to Asia. Was introduced in order to control erosion.
Zebra Mussels
Native to the lakes of Russia. Detected in the Great Lakes in 1988. Invasive in that they multiply rapidly and can filter large amounts of zooplankton, robbing native young fish of food. Introduced accidently
0ne of the 4 major major threats to biodiversity ,practice of harvesting or hunting to such a degree that remaining individuals may not be able to replenish the population, large organisms with low reproductive rates are especially susceptible.
Extinction Vortex
A downward population spiral in which positive-feedback loops of inbreeding and genetic drift cause a small population to shrink, and unless reversed, become extinct.
continued breeding of individuals with similar characteristics to maintain the desired characteristics of a line of organisms, can bring out many harmful recessive traits.
Genetic Drift
changes in the gene pool of a small population due to chance. Tends to reduce genetic variation.
estimate of the smallest number of individuals necessary to ensure the survival of a population in a region for a specified time period, USUALLY estimated by a computer model.
aim: to determine the minimum size of population that will guarantee species survival. types: subjective assessment, rule of thumb, analytical population models, computer simulations, displayed in percentages. Allows biologists to expolre the potential consequences of alternative management plans.
Genetic Variation
the many different genetic combinations an individual gamete can produce, is the key issue in the small population approach, because the total size of a population may be misleading because only certain members will pass their alleles to their offspring.
Effective Population size
An estimate of the size of a population based on the numbers of females and males that successfully breed; generally smaller than the total population. The equation is ( 4 x M X F) / (M+F)
Grizzly Bear
(Ursus arctos horribilis) The bear considered to probably be the most dangerous animal in North America, the first population viabilty anaylses was performed in 1978 by Mark Schaffer of Duke University in Yellwstone National Park..
Small population approach
One of the two approaches used to fight the biodiversity crisis, the approach to species conservation concerned with the factors that drive a small population to extinction, such as genetic drift, inbreeding, etc., instead of the ecosystem.
Declining Population approach
One of the two approaches used to fight the biodiversity crisis, , a proactive approach to species conservation that focuses on detecting, diagnosing and preventing population declines in order to keep the population above a minimum viable size. Mainly on enviromental factors.
boundaries between well-defined ecosystems, have characteristics of their own, and some animals like deer can flouish when its range is broadened, which usually will signal a loss of the interior species.
Landscape Ecology
the study of past, present, and future patterns of landscape use, as well as ecosystem management and the biodiversity of interacting ecosystems
(Molothrus ater), an example of an eged adapted species that lays eggs in the nests of others brds, poarticulary migratory songbirds and makes them take care of their young. Increasing parasitism of this bird is correlate with declining population of the brirds host species.
Biological Dynamics of Forest Fragments Project
A long term project that has focused on the effects of logging within the amazon basin , they have discovered that species that have adapted to the interior show the greatest declines in the smallest fraagments.
Movement Corridor
A series of small clumps or a narrow strip of quality habitat (usable by organisms) that connects otherwise isolated patches of quality habitat. Can be a deciding factor in preserving biodiversity, depending on whether or not they help tranport diseases as well.
Biodiversity Hot Spot
A relatively small area with an exceptional concentration of endemic species and a large number of endangered and threatened species
Endemic Species
Species that is found in only one area. Such species are especially vulnerable to extinction.
Biotic Boundary
The area that is needed to prevent the extinction of a species.
Legal Boundary
The actual area put aside to try and prevent the extinction of a species.
Zoned Reserves
An extensive region of land that includes one or more areas undisturbed by humans surrounded by lands that have been changed by human activity and are used for economic gain
the act of treating waste or pollutants by the use of microorganisms (as bacteria) that can break down the undesirable substances
A bacterium that is used in the process of bioremediation to help clean up oil spills on beaches.
Biological Augmentation
an approach to restoration ecology that uses organisms to add essential materials to a degraded ecosystem, an example is the rapid growth of indegenous plaant communities along roadsides in Peurto Rico using Albizzia procera(a nonnative plant)
Albizzia procera
A nonnative plant( to Puerto Rico) that thrives in nitrogen poor soils and colonize roadsides and was used in the biological augmentation.
(360-260mya) caused by initial expansion of first forests that depleted large amounts of atmospheric CO2, is a semi desert located in South Africa
Sustainable Development
Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
E. O Wilson
published Sociobiology: The New Synthesis- applies the principles of evolutionary biology to the study of social behavior in animals, also coined " biophilia", which he says is innate.
A ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening, and in consequence the amount of light entering the eye
Action potentials that reach the brain via sensory neurons
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events. Only exists within the brain
Axial Skeleton
The part of the skeleton forms the main trunk of the body and is composed of the skull, spinal column, ribs, and breastbone
Sensory Reception
detection of a stimulus by sensory cells, what sensation and perception begin with.
Sensory Receptors
specialized cells that detect certain forms of energy, usually specailized neurons or epithelial cells that exist in groups or with other sensory organs like eye and ear.
sensitive to stimuli arising outside body (touch, pressure, pain receptors)
sense internal environment; monitor inside world; such as glucose and oxygen levels in the blood
Hair Receptor
nerve endings around root of hair in hairy skin, small receptive field, either slowly or rapidly adapting - vibrissae, whiskers, are specialized hair follicle receptors
Stretch Receptor
sensory receptor in a muscle that responds to stretching of tissue; send information to CNS concerning lengths and tensions of muscle fibers
the amount of increase in signal power or voltage or current expressed as the ratio of output to input
The processing of sensory information, occurs as soon as info is recieved, also includes sensory adaptation
Process whereby the pain impulse travels from the receiving nociceptors to the spinal cord
Sensory Transduction
receptor cell converts exposure from stimulus into a change in electrical potential across its membrane
Receptor Potential
A slow, graded electrical potential produced by a receptor cell in response to a physical stimulus
Sensory adaptation
Diminished sensitivity as a consequence of constant stimulation
A sensory receptor that responds to mechanical disturbances, such as shape changes (being squashed, bent, pulled, etc.). Mechanoreceptors include touch receptors in the skin, hair cells, in the ear, muscle spindles, and others.
sensory receptor that detects the presence of a specific chemical
Electromagnetic receptors
detect electromagnetic energy such as light, electricity, and magnetism; ex: photoreceptors
respond to changes in temperature. They conduct sensations along the same pathway that carry pain sensations.
light sensitive cells (rods and cones) that convert light to electrochemical impulses
Pain receptors
Respond to tissue damage; triggered by mechanical, electrical, thermal or chemical energy
Receptors in the skin that give rise to the sense of pain; they respond to various forms of tissue damage and to temperature extremes.
Muscle Spindle
Distributed throughout the belly of the muscle. They function to send information to the nervous system about muscle length and rate of change of its length.
Chemical signals released by organisms to communicate with other members of their species. ________ are often used by animals as sexual attractants.
Rods and Cones
visual receptors that transduce light neural impulses. The rods are concentrated in the periphery of the retina, the cones in the fovea.
the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
a gravitationally-sensitive vesicle lined with sensory cells and containing dense bodies; found in many invertebrates(cnidarians)
Grains of sand or dense granules that determine gravity in invertebrates
Tympanic Membrane
The eardrum. A structure that separates the outer ear from the middle ear and vibrates in response to sound waves.
Outer Ear
The portion of the ear consisting of the pinna and the external auditory canal. The outer ear is separated from the middle ear by the tympanic membrane (the eardrum).
Middle Ear
the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window
Inner Ear
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.
Oval Window
membrane at the enterance to the cochlea through which the ossicles transmit vibrations
the stirrup-shaped ossicle that transmits sound from the incus to the cochlea
Middle Ear
the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window
Semicircular Canals
three canals within the inner ear that contain specialized receptor cells that generate nerve impulses with body movement
Eustachian Tube
A narrow tube between the middle ear and the throat(pharynx) that serves to equalize pressure on both sides of the eardrum
throat; passageway for food to the esophagus and air to the larynx
the snail-shaped tube (in the inner ear coiled around the modiolus) where sound vibrations are converted into nerve impulses by the Organ of Corti
The organ of Corti
The actual hearing organ found within the cochlea, consists of hair cells, the receptor cells of the ear.
basilar membrane
A structure that runs the length of the cochlea in the inner ear and holds the auditory receptors, called hair cells.
Vestibular Canal
the sensory system that provides the dominant input about movement and equilibrioception and contributes to our balance and our sense of spatial orientation
Round Window
one of the two openings into the cochlea of the inner ear; closed off from the middle ear by the round window membrane, which vibrates with opposite phase to vibrations entering the cochlea through the oval window; allows fluid in the cochlea to move, which in turn ensures that hair cells of the basilar membrane will be stimulated and that audition will occur
the bodily fluid that fills the space between the bony labyrinth and the membranous labyrinth of the inner ear
the property of sound that varies with variation in the frequency of vibration
larger of two sacs within the membranous labyrinth of the vestibule in the inner ear (uter = leather bag)
smaller of two sacs within the membranous labyrinth of the vestibule in the inner ear ( small bag)
Lateral Line System
A mechanoreceptor system consisting of a series of pores and receptor units (neuromasts) along the sides of the body of fishes and aquatic amphibians; detects water movements made by an animal itself and by other moving objects
cluster of hair cells w/ cilia embedded in cupula that detect the movemnt of water - for fish and amphibians (functional cell), resemble the ampullae found in human semicircular canals
enlargement at the base of each semicircular canals. at the base is where the receptors are found
Weberian Apparatus
A series of bones that conduct the vibrations from the swim bladder to the inner ear.
gelatinous structure, as the head moves in different planes, this moves with cravity causing hair cells to bend ( there are no otoliths in the semicirucular canals)
or taste, provides information about the food and liquids that we consume.
the sense of smell, which occurs when receptors in the nose respond to chemicals
these tiny hairs found on an insects legs and antennae give insects their senses of touch, balance, hearing, smell, taste and temperature, allows insect to quickly identify chemicals
recently recognized and only defined as "savory", "meaty", "delicious"; when certain AA (glutamate, aspartate, MSG) bind to specific receptor proteins
excites receptors in the brain; synthetic; people sensitive to it have problems when ingested, can act as agonist for AMPA and NMDA receptors
Structures on the tongue containing groups of taste receptors, or taste buds
Is a protein that a odorous substance or odorant binds to after diffusing into the layer of mucus coating the nasal cavity, triggerd a signal transduction pathway involving a G protein, adenylyl cyclase, and cyclic AMP, which opens channels in the plasma membrane that are permeable to Na+ and Ca2+, which depolarizes the membrane and causes the receptor cell to generate an action potential.
A molecule that activates an olfactory receptor and causes the transmission of information about a smell.
A small cup with light-sensitive surface backed by light-absorbing pigment, in contrast to compound eyes, which are image forming., Is only open in a particular directions ( one left and slightly forward and the other right forward) Used by planarians to avoid predators because they are then able to distinguish the direction of the light and move away from it.
Compound Eyes
Found in Insects and Crustaceans(Arthropods) and some polycheate worms(Annelida), it consists of several thousand light detectors(ommatadia), each with its own lens, which directs light from a tiny portion of the visual field , where they differences in angles and intensity result in a mosiac image, very capable of detecting very fast movements (330) times per second
In this functional structure of the compound eye , the cornea and the crystalline cone focus light into the rhabdom(stick of pigmented plates onside a circle of photoreceptors), which traps light and guides it to the photoreceptors producing a mosiac image of different intensities and angles.
Single- lens eyes
Found in jellies, spiders, molluscs, and most polycheates, works on a camera like principle , the iris changes the diameter of the pupil, and behind the pupil a single lens focuses light on a layer of photoreceptors, and muscles in the lens can also move the lens forward backward or forward.
"the outermost layer is the tough connective tissue": maintains the shape of the eye: also referred to as the 'white' of the eye, cornea is the outermost part of it in the front of the eye.
The darkly pigmented middle layer of the eyeball, found between the sclera (outer layer) and the retina (inner layer). The interior forms the dougnout shaped iris
The curved protective layer through which light rays enters the eye. Light rays are bent here as well as in the lens.
clear mucous membrane consisting of cells and underlying basement membrane that covers the sclera (white part of the eye) and lines the inside of the eyelids. Protects eyes from foreign bodies.
The light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information, the photoreceptors in this part leavres the eye at the optic disk
Optic Disk
A hole in the retina where the optic nerve fibers (and visual information) exit the eye. Because you can not see the part of an image that falls on this hole, it is also known as the blind spot.
The transparent structure behind the pupil that changes shape(accommodation) to help focus images on the retina.
Ciliary Body
A portion of the vertebrate eye associated with the lens. It produces the clear, watery aqueous humor that fills the anterior cavity of the eye, and together with the lens it separates the eye into two cavities.
the process by which the eye's lens changes shape to focus near(by beoming more spherical) or far objects (by becoming flatter) on the retina
Retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond. (125 Million) Mainly concentrated in the peripheral part of the retina., and NOT found in the fovea. Consist of retinal bounded to an opsin.
Retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations. (6 million) Less sensitive., MOST DENSE in the fovea. Consist of retinal bounded to an opsin . 3 classes red green, blue RGB.
Suspensory Ligaments
Bands of collagen that connect the lens to the ciliary muscles(near sight relax), (far sight pull against lens)
area consisting of a small depression in the retina containing cones and where vision is most acute
A visual pigment consisting of retinal and opsin. When rhodopsin absorbs light, the retinal changes shape and dissociates from the opsin, after which it is converted back to its original form.
The protein part of the visual pigment molecule, to which the light-sensitive retinal molecule is attached.
A chemical derived from vitamin A found in the pigment proteins of the rod photoreceptors of the retina. Retinal changes conformation when it absorbs light, triggering a series of reactions that ultimately result in an action potential being sent to the brain.
Activation of rods by light bleaches photopigment (changes wavelengths absorbed by rhodopsin) - no longer respond at particular light intensities
Are the photoreceptor proteins found in the cone cells of the retina that are the basis of color vision. 3 types (RED, BLUE, GREEN). An absence of one diminishes the relative capacity of the brain's reception on differentual hues.Color blindness is due to the lack of these cone types.
The frequency of the wavelength of color; what we normally refer to as the color of an object.
Bipolar Cells
Located in the retina, has specialized neuron located in the eye; as one dendrite and one axon; connects rods/cones which when stimulated are depolarized or hyperpolarized depending on the type of photo-receptors they contain, and continually release the neurotransmitter Glutamate.
a major excitatory neurotransmitter in the brain that increases the likelihood that a postsynaptic neuron will fire; important in learning, memory, neural processing, and brain development.
Ganglion Cells
neurons that connect the bipolar cells to the optic nerve; an interneuron; one million in each eye; summarizes and organizes data from rods/cones and sends it to the brain, most of its cells go to the Lateral Geniculate nuclei in the Thalamus.
Amacrine Cells
they link bipolar cells to other bipolar cells and ganglion cells to other ganglion cells.
Horizontal Cells
Specialized retinal cells that contact both the receptor cells and the bipolar cells
Lateral Inhibition
Exaggerates the sense of contrast that occurs when light hits the photoreceptors. Occurs when an illuminated cone or rod stimulates a horizontal cell, which then inhibits more distant photoreceptors.
Receptive Field
Describes all the rods and cones that feed information to one ganglion, the larger the less sharp of the image , because of less specificty on exactly where light struck the retina.
Optic Chiasm
The point at which the optic nerves from the inside half of each eye cross over and then project to the opposite half of the brain
Lateral Geniculate nuclei
The destination in the thalamus for most of the ganglion cell axons that form the optic nerves. This area has neurons that extend into the primary visual cortex (which is located in the occipital lobe of the cerebrum)
Primary Visual Cortex
The region of the cerebral cortex that receives information directly from the visual system; located in the occipital lobe of the cerebrum.
Hydrostatic Skeleton
A fluid skeleton in many soft-bodied invertebrates, including annelids, that allows an organism to change shape but not volume.
A rythmic, wavelike motion that progressively moves through a tube organ such as the small intestine, or a type of movement produced by contracting the circular muscles and relaxing the longitudinal muscles.
Complex carbohydrate that makes up the cell walls of fungi; also found in the external skeletons of arthropods
The exterior protective or supporting structure or shell of many animals (especially invertebrates) including bony or horny parts such as nails or scales or hoofs, may include chitin.
A process in ecdysozoans in which the exoskeleton is shed at intervals, allowing growth by the production of a larger exoskeleton.
member of the group of animal phyla with protosome development that some systematsts hypothesize form a clade, including many molting animals
A hard skeleton buried within the soft tissues of an animal, such as the spicules of sponges, the ossicles of echinoderms, and the bony skeletons of vertebrates
Found in echinoderms, it is the Magnesium carbonate and calcium carbonate bound by protein fibers,
Appendicular Skeleton
One of the two main parts of the human skeleton; includes the bones of the arms and legs and associated structures, such as the shoulders and hip bones, makes motion possible and protects the organs of digestion, reproduction, and excretion
Cross Sectional
The strength of the skeleton depends on the _____________ area, which increases with the square of its diameter.
Body Posture
Related to the extent to which we face or lean toward or away from others, is more important than weight in mammals and birds.
tough connective tissue that joins skeletal muscles to bones For Example (Achilles Tendon)
Skeletal Muscle
Name the muscle type based on the histological features: • Actin and myosin in sarcomeres; striated; multinuclear; lacks gap junctions; troponin:calcium binding; T tubules and SR forming triadic contacts; highest ATPase activity; no calcium channels
Micorsopic, fiber-like structures that occupy most cytoplasm in skeletal muscle cells, composed of two myofilaments( thin filaments and Thick filaments
Smaller structure within sacromeres; the muscle equivalents of the actin or myosin containing microfilaments (THIN and THICK filaments)
Thin filaments
Composed of 2 strands of actin and a regulatory protein(troponin); each actin has an active site that can interact with myosin; active sites are covered by tropomyosin strands, which are held in place by troponin.
Thick filaments
Composed primarily of myosin; , extend the entire length of the A-band; contain twisted myosin subunits, contain strands that recoil after stretching, myosin molecules: tail- binds to other myosin molecules, head= made of 2 globlular protein subunits reachest nearest thin filament
Troponin Complex
The regulatory proteins that control the position of tropomyosin on the thin filament., When Ca2+ is there it causes a conformational change in tropomyosin.
A helical protein that winds around actin helices in skeletal and cardiac muscle cells to form the thin filament of the sarcomere. In the absence of Ca2+, it covers the myosin-binding sites on actin and prevents muscle contraction. When calcium binds to a troponin complex, a conformational change in tropomyosin occurs so that the myosin-binding sites are exposed and muscle contraction can occur.
The band of the sarcomere that extends the full length of the thick filament. Includes regions of thick and thin filament overlap, as well as a region of thick filament only(H zone). It alternate with I bands to give skeletal and cardiac muscle a striated apperance. This band does NOT shorten during muscle contraction.
the smallest contractile unit of a muscle fiber - the functional unit of skeletal muscle; average 2um long; the region of a myofibril between 2 successive Z discs
Z lines
Thin filament (thin horizontal lines), Thick filament (darker horizonal lines). From one z-line to another is one sarcomere
I Band
The region of the sarcomere made up ONLY of THIN filaments. It is bisected by a Z line.These bands alternate with A bands to give skeletal and cardiac muscle a striated appearance. I bands get shorter (and may disappear completely) during muscle contraction.
H Zone
The region at the center of an A band of a sarcomere that is made up of myosin only. This zone zone gets shorter (and may disappear) during muscle contraction.
Sliding Filament Model
The theory explaining how muscle contracts, based on change within a sarcomere, the basic unit of muscle organization, stating that thin (actin) filaments slide across thick (myosin) filaments, shortening the sarcomere; the shortening of all sarcomeres in a myofibril shortens the entire myofibril
Creatine Phosphate
An energy storage molecule used by muscle tissue. The phosphate from creatine phosphate can be removed and attached to an ADP to generate ATP quickly.
An anerobic metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP, can suppurt about a minute of sustained contractions.
A neurotransmitter that enables muscle action, learning, and memory, is released and depolarizes the muscle fiber causing an action potential which then spreads to the transverse tubules
Transverse Tubules
System of tubules that provides channels for ion flow throughout the muscle fibers to facilitate the propagation of an action potential.
Sarcoplasmic Reticulum
The smooth ER of a muscle cell, enlarged and specialized to act as a Ca2+ reservoir. The SR winds around each myofibril in the muscle cell.
Amyotrophic lateral sclerosis
Progressive muscle atrophy caused by hardening of nerve tissue on the lateral columns of the spinal column (Lou Gehrig disease)
Motor Unit
A single neuron and all the muscle fibers it stimulates
Increase in number of motor units activated as stimulation intensity increases
a sustained muscular contraction resulting from a rapid series of nerve impulses
Oxidative Fibers
Muscle fibers with many mitochondria, a lot of myoglobin, and a high capacity of oxidative phosphorylation, surrounded by many small blood vessels (to deliver O2)
Glycolytic Fibers
Muscle fibers w/ a little mitochondria and myoglobin, a lot of glycolytic enzymes and glycogen, and surrounded by few blood vessels, (WHITE)
A globular protein found in muscle tissue that has the ability to bind oxygen.Helps to store oxygen in the muscle for use in aerobic respiration (it does not move, just stays there). Muscles that participate in endurance activities (including cardiac muscle) have abundant supplies of of this(which is red)
Cardiac Muscles
A striated involuntary muscle that is found in the heart.
Intercalated Disks
These structures branch and connect cardiac cells. They contain specialized gap junctions and coordinate muscle contractions.
Smooth Muscle
A muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart), have dense bodies to which thin filaments are attatched , contraction caused by Ca2+ binding to calmodulin.
Dense Bodies
smooth muscle...thin filaments in smooth muscle are anchored directly to the sarcolemma or to protien muscles called _________
A cyoplasmic Ca2+-binding protein that is particularly important in smooth muscle cells, where binding of Ca2+ allows for the activation of a myosin light-chian kinase, the first step in smooth muscle cell contraction.
Found in clam adductor muscles, allows month long contraction with very limited energy
Motion or the potential of motion of a living organism
Spindle-shaped; elongated, thick in the middle, and tapered at both ends, such as the shape of a smooth muscle cell or a muscle spindle, or of a swimmer.
The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the is responsible for automatic survival functions, consists of a stalk with caplike swelling at the anterior end of the spinal cord, consists of 3 parts(medulla oblangata, pons, and the midbrain) which function in homeostasis, coordination, and conduction of information to higher brain centers.
a selective-serotonin reuptake inhibitor commonly prescribed as an antidepressant
The individual cells that are the smallest units of the nervous system, Approximetly 100 billion(10^11) in the brain.
Functional MRI
Allows researchers to scan areas of the brain while a participant performs a physical or cognitive task
In prokaryotes and protists, the movement toward or away from a chemical stimulus, such as the movement toward food or away from a toxin
Cambrian Explosion
By the time of the _________, 500 million years ago , systems of neurons allowed animals to sense and rapidly move in essentially a modern day form.
All animals EXCEPT ________ have some type of nervous system, also they are they only phyla that are "not true tissue" animals.
Radially symetrical invertebrates (Think Polyp/Medusa), which have the simplest nervous system, one that has a diffuse nerve net.
Nerve Net
A diffuse web of inconnected nerve cells which control nervous responses in cnidarians
Neural "cables" containing many axons. These bundled axons, which are part of the peripheral nervous system, connect the central nervous system with muscles, glands, and sense organs, more complicated then nerve nets.
Animal phyla that has a nerve net in each arm conected by a radial nerve to a central nerve ring. Which allows this phylum to be more adept at making movements.
An evolutionary trend toward the concentration of sensory equipment at the anterior end of the body. Greater ___________ usually means greater, more complex neurological structures.
The portion of the vertebrate nervous system consisting of the brain and spinal cord(In annelids(like leaches), in more complex creatures behavior is regulated by ganglia
groups of nerve cell bodies that coordinate incoming and outgoing nerve signals
The sensory and motor nerves that connect the brain and the spinal cord to the rest of the body, 12 Cranial Nerves and 31 Spinal Nerves, broken into two parts(Somatic and Autonomic)
Phylum Mollusca, have no distinct head, clings to rocks, scrape algae with radula, one broad muscular foot, little or no cephalization and very simple sense organs, in contrast to moving cephalopod( squids and octopi) which have complicated nervous systems, these molllusca show how nervous system organization correlates to an animals lifestyle.
Central Nerve Ring
Found in starfish and other echinoderms... manifests as a ring of nerves in the center of the organism to which all radial/peripheral nerves attach
Sensory Input
1st stage of information processing by Nervous System, where nervous system receives information from environment through stimuli (inside and outside of the body) which is then sent to the CNS via Sensory Neurons.
2nd Stage of information processing by Nervous System(and the complex), where interneurons analyse and interpet the sensory input taking into account the immediate context as well as what has happened in the past.
Motor Output
3rd and final stage of information processing by Nervous System, where motor neurons take the signal from the interneurons and transmitt them into effector cells (muscle or endocrine cells).
An automatic and often inborn response to a stimulus that involves a nerve impulse, is the simplest way to study nervous sytem
Effector Cells
The muscle cells or gland cells(endocrine) that actually carry out the body's responses to stimuli.
Cell body
Contains the nucleus, where most of the molecules that provide energy neuron needs to survive and function is manufactured
Axon Hillock
The conical region of a neuron's axon where it joins the cell body; typically the region where nerve signals (action potential) is generated.
Myelin sheath
A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next, Mutiple Scedlrosis attacks this in PNS(Schwann Cells) .
The bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body
the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
Postsynaptic Cell
Cell recieveing the neurotransmitter, so that sodium ions can go in and Action potenital may occur
Presynaptic Cell
synaptic surface where neurotransmitter release occurs.
chemical messengers that traverse the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.
Glia Cells provide myelination in CNS, elctrically insulates certain axons, & speeds up rate of electrical signals, MS targets these.
Schwann Cells
Part of the neuron in the (PNS) that produces the myelin sheath; functions in repair and regeneration of damaged nerves; wrap around the axon; aid the myelin in insulation
Star shaped cells found throughout the CNS, cleaning up debris in the extracellular space and removing neurotransmitters from the synaptic cleft, connects neurons to nearby cappilaries, components of the blood-brain barrier, and along with radial glia produce stem cells that help produce more glia and neurons.
Blood Brain Barrier
Blood vessels (capillaries) that selectively let certain substances enter the brain tissue and keep other substances out, formed by astrocytes (glia) which induce the formation of tight junctions between cells that line the capillaries in the brain and the spinal cord.
Radial Glia
Special glia with fibers that grow radially outward from the ventricular zone to the surface of the cortex; provide guidance for neurons migrating outward during brain development, and can also act along with astrocytes to produce stem cells which can generate neurons and other glia.
From the Greek Word meaning "glue". Cells that support, nurture, and insulate neurons, remove debris when neurons die, enhance the formation and maintenance of neural connections, and modify neuronal functioning, outnumber neurons 10 to 50 times. 4 types (Oligodendrocytes, Astrocytes, Radial Glia, and Schwann Cells)
Membrane Potential
The charge difference between a cell's cytoplasm and the extracellular fluid, due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances. In Neurons it is usuakky -60 to -80 mV when the cell is not transmitting signals.
A thin electrode made of wire or glass (with a salt solution) that can measure the electrical activity of a single neuron by using a micropositioner to insert an extemely fine tip into the cell, and then an oscilloscope or computer measuresa the voltage
Resting Potential
An electrical potential established across the plasma membrane of all cells by the Na+/K+ ATPase and the K+ leak channels. IN most cells, the r__________ is approximately -70 mV with respect to the outside of the cell.
Sodium Potassium Pump
A pump that actively maintains the gradient of sodium ions (Na+) and potassium ions (K+) across the plasma membrane of animal cells . K+ concentration is low outside animal cell and high inside the cell. Na+ concentration is high outside an animal cell and low inside the cell. Maintains these concentration gradients using the energy of one ATP to pump three Na+ out and two K+ in.
Equilibrium Potential
When the net diffusion of an ion down its conc. gradient slows, and then stops, because of the potential difference. Nernst equation converts the concentration difference of an ion into a voltage measurement.
Ligand Gated ion channels
Found at synapses and open or close when a specific chemical, such as a neurotransmitter, binds to the channel. THINK Tyrosine Kinase/ other kinases